Belgian Physical Society Magazine B 1- 2018

2018 General Scientific Meeting of the BPS: April 11th in UAntwerpen. Research Activitities in Physics in Belgium

BΦ CONTENT

Editorial 2 News 3 BPS Scientific Meeting 2018 3 BPS Best Master Thesis Awards 2018 3 Featured Articles 5 Research Activities in Astronomy and Astrophysics in Belgium. 5 (Y. Fremat et al.) Research Activities in Plasma Physics in Belgium. (R. Weynants) 20 Research Activities in Computational Physics in Belgium (X. 25 Gonze & G. Rignanese) Research Activities in Hard Condensed Matter and Semicon- 35 ductor Physics in Belgium (E. Janssens & Y. Bruynseraede) Sponsors 51

BΦ - Belgian Physical Society Magazine

Editor in Chief Fabrice Louche

Lay-out Fabrice Louche, Sabine Van Doorslaere

Belgische Natuurkunde Vereniging/Société Belge de Physique v.z.w./a.s.b.l.

President Jef Ongena

Vice-President Gilles De Lentdecker Secretary Jean-Claude Jodogne Adjunct Secretary Fabrice Louche Accountant Yves Caudano

Board Members: Bart Cleuren, Michele Coeck, Evelyne Daubié, Karen Feyen, Ewald Janssens, Raymond Koch, Peter Schlagheck, Niels Schoon, Jacques Tempere, Michael Tytgat, Xavier Urbain, Lisanne Van Puyvelde, Michel Voué, Roger Weynants

BΦ - Belgian Physical Society Magazine - 01/2018 1 BΦ EDITORIAL

Hawking besides Newton in Westminster Abbey

Professor Stephen Hawking died peacefully on 14 March, aged 76, at his home in Cambridge, precisely 139 years after the birthday of Einstein. He was a brilliant and extraordinary mind with courage, humour and an exemplary determination.

Professor Hawking arrived at the University of Cambridge in 1962 as a Ph.D. student. In 1974, he became one of the youngest fellows of Britain’s most prestigious scientific body, the Royal Society, at the age of 32. Five years later, he was appointed Lucasian Professor of Mathematics at Cambridge University. Previous holders of this prestigious chair were the 17th-century British scientist Isaac Newton, and the 20th century prodigy Paul Dirac.

He was a scientist with a creative and nonconformist mind, who explained the Big Bang and black holes in his best-selling book "A Brief History Of Time". His most renowned discovery is that black holes, not gaining mass in another way, can evaporate to essentially nothing. This phenomenon better known as "Hawking radiation", turned him nearly instantly into one of the most famous physicists of our time.

Prof Hawking was diagnosed in 1964 with which was then identified as the fatal degenerative motor neurone disease ALS, short for "amyotrophic lateral sclerosis". He was then 22 and was given a few more years to live. Soon afterwards, rather than succumbing to depression, he began to set his sights on some of the most fundamental questions concerning the physical nature of the universe. In due course, he would achieve extraordinary successes despite his severe physical disability. Against traditional medical wisdom, he managed to live another 55 years. The image of Stephen Hawking in his motorised wheelchair, with head contorted slightly to one side and hands crossed over to manage the controls, caught the public imagination, as a true symbol of "the triumph of mind over matter", a very pointed citation by Roger Penrose, with whom he was jointly awarded the Eddington Medal of the Royal Astronomical Society in 1975.

He received numerous other prizes and awards, the last being the "Pride of Britain Award, for his contribution to science and British culture", in 2016. After receiving the award from Prime Minister Theresa May, Hawking humorously requested that she not seek his help with Brexit...

The funeral for Professor Hawking took place on the 31st March in the church of the University of Cambridge, Great St Mary’s. His ashes will be placed, besides the other giants in science, Newton, Maxwell and Dirac, in Westminster Abbey, London.

With my best regards,

Jef Ongena, BPS President

BΦ - Belgian Physical Society Magazine - 01/2018 2 BΦ NEWS

BPS General Scientific Meeting 2018

It is our pleasure to announce the General Scientific Meeting 2018 of the Belgian Physical Society, which will take place on Wednesday 11th April, 2018 at Antwerp University. This annual one-day conference brings together physicists from Belgian universities, Belgian high schools and higher education schools, as well as from Belgian industries and companies. Its main aim is to establish links and stimulate collaborations between research groups working at different research institutions within Belgium, and to provide a platform for Belgian high school teachers to get updated on the current state of the art in physics.

Programme

• 8:00: Registration and Welcome coffee with croissants

• 9:00: Invited Plenary Lectures – 9:00-9:15 Welcome by Jef Ongena, BPS president – 9:15-10:00 Paulo Giubellino (Facility for Antiproton and Ion Research in Europe & GSI) : FAIR - The Universe in the Laboratory – 10:00-10:45 Lieven Vandersypen (QUTech & Kavli Inst. for Nanoscience, TUDelft): A "Spins-inside" Quantum Processor

• 10:45-11:15: Coffee break

• 11:15-12:40: Young Speakers Contest – 11:15-11:25: Introduction & European Physical Journal (sponsor) – 11:25-11:50: Boris Brun-Barrière (UCL) - Wigner and Kondo physics in quantum point contacts revealed by scanning gate microscopy – 11:50-12:15: Jonas Bekaert (UAntwerpen) - Monolayer materials as an ideal platform for enhanced superconductivity – 12:15-12:40: Gwenhaël de Wasseige (VUB) - Solar Flare Neutrinos in the Multi Messenger Era

• 12:40-14:00: Buffet walking lunch & poster viewing

• 14:00-16:30: Parallel sessions – Astrophysics, Geophysics, and Plasma Physics (Auditorium O.01) – Biophysics, statistical physics and medical physics (Auditorium O.02) – Condensed Matter and Nanophysics (Auditorium O.03) – Fundamental interactions, Particle and Nuclear physics (Auditorium O.04)

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• – Quantum physics, atoms and optics : (Building Q - Aula Fernand Nedee) – Physics and Education (Building Q - Promotiezaal)

• 16:30-17:15: Poster session

• 17:15-17:30: Closing session and prize ceremony

• 17:30-18:30: Reception and sandwich dinner

• 18:30-20:00 Evening event: Movie "De Kwantumrevolutie" (Promotiezaal, building Q)

The conference will take place on the Campus Drie Eiken of Antwerpen University. The venue is "Aula Fernand Nedee", also known as building Q. There are many parkings scattered around the campus. More details on how to reach the conference site is here: https://www.uantwerpen.be/en/conferences/belgian-physical-society-2018/.

BPS Best Master Thesis Awards 2018

We are proud to announce the three laureates of the BPS 2018 Best Master Thesis Award (in alphabetical order):

• Paul Coppin (VUB) - InIce Veto Studies for the Future IceCube-GEN2 Neutrino Observatory

• Pablo Correa (VUB) - Comparison of Statistical Methods to Evaluate the IceCube Discovery Potential for Steady Point Sources

• Sacha Schiffmann (ULB) - Relativistic semi-empirical-core-potential calculations in alkali-like systems using Lagrange meshes

The winners will receive their prize during the closing session of the BPS General Scientific Meeting on April 11th in Antwerp.

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Research Activities in Astronomy and Astrophysics in Belgium

Y. Fremata, S. Van Eckb, C. Aertsc, M. Baesd, D. Berghmansa, C. Bruyninxa, S. Buitinke, M. Davidf, P. Defraignea, V. Dehanta, J. De Keyserg, S. De Rijked, A. Fuzfah, M. Groenewegena, T. Hertogi, E. Javauxj, A. Jorissenb, R. Keppensk, K. Kolenbergf, K. Lefeverg; A. Lemaitreh, A. Lobera, E. Neefsg, D. Pourbaixb, P. Quineti, G. Rauwm, C. Ringevaln, J. Surdejo, M. Tytgatp, R. Van der Lindena, P. van Hoofa, T. Van Hoolsta.

aROB: http://www.astro.oma.be/ bULB: http://www.astro.ulb.ac.be cKULeuven/IvS: http://fys.kuleuven.be/ster dUGent: http://www.astro.ugent.be/ eVUB: http://we.vub.ac.be/nl/astronomy-and-astrophysics fUAntwerpen: http://astro.ua.ac.be/ gBIRA-IASB: http://www.aeronomie.be/ hUNamur: www.naxys.be iKULeuven/ITF: https://fys.kuleuven.be/gwc/ jULiege` (UR GEOLOGY): http://www.facsc.uliege.be/cms/c 3172635/en/ur-geology kKULeuven/CmPA:http://wis.kuleuven.be/cpa/ lUMons: http://web.umons.ac.be/∼astro/indexgb.shtml mULiege:` http://star.ulg.ac.be nUCL: https://uclouvain.be/en/research-institutes/irmp/cp3 oULiege` (AEOS): http://www.aeos.ulg.ac.be pULB: http://www.ulb.ac.be/sciences/physth/

12The last years have seen the construction of im- the exploitation of Space missions. On the interna- portant ground telescopes and instruments, while tional level, these achievements allowed the Belgian Belgian astronomers also continued to enforce their astronomical community to strengthen an excel- participation in the preparation, development, and lent reputation. Their implication in ambitious re- search projects allowed our scientists to become 1The Belgian National Committee for Pure and Ap- main actors to major breakthrough in various fields plied Physics (BNCPAP) is responsible for the con- of astronomy. Most of the projects that made these tent of the present review article. For any re- contributions possible have been funded by grants mark please contact the secretary of the BNCPAP from the regions, from the Belgian Science Policy ([email protected]). 2 Office (BELSPO), as well as from the European Re- This text is an update of the overviews of Belgian 3 research in Astrophysics written by H. Oejonghe in search Council (ERC ). Among these, ERC2 grants 2005 (Physicalia Magazine, 27, 275-280 and by A. are the most prestigious research grants in Europe. Jorissen in 2011 (Bo, Belgian Physical Society Maga- zine, 4, 33-42). Based in part on a recent status report 3More information about the awarded projects is given requested by BELSPO, its length was substantially in the text. To designate the type of grant we adopted increased with respect to our regular entries and it the following acronyms: StG = Starting Grant, CoG exceptionally has a multi-authorship. = Consolidator Grant, AdG = Advanced Grant.

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They fund researchers of any nationality and age laxes of faint nearby objects. In addition, the ILMT who wish to pursue frontier research, and provide will provide a huge amount of quasar light curves a high-level science stature to the person, the labo- that will allow astronomers to statistically investi- ratory, and the country to which it is given. Even gate the nature of the intrinsic variability of quasars more encouraging is to note that a good part of with the aim to get information on the central en- these grants have been awarded to women. It makes gines. These projects should provide ideal targets our country quite unique and marks the beginning of opportunities for follow-up direct imaging or of a new era for astronomy in Belgium. spectroscopic observations with the ARIES 3.6m telescope, as described below. The ILMT is open to all Belgian astronomers in the spirit of collaborative 1 New ground-based projects.

telescopes The 1.2m Flemish Mercator telescope5, located at the Roque de los Muchachos observatory (La Palma, 1.1 Belgian telescopes (ordered by Canary Islands) and run by KULeuven/IvS, already decreasing mirror size) mentioned in the 2005 and 2011 reports, has contin- ued its operations. It is equipped with the highly The International Liquid Mirror Telescope (ILMT4) efficient HERMES (high-resolution fibre-fed spec- has been proposed by an international consor- trograph) spectrograph (Raskin et al., 2011, A&A tium initiated by astrophysicists from the Insti- 526, A69). The design, building and integration of tut d’Astrophysique et de Geophysique (Liège Uni- this luminous, high-resolution spectrograph were versity, ULiège), and comprising the following joint efforts of the Belgian institutes at the univer- institutions: the Royal Observatory of Belgium sities of Leuven and Brussels (ULB) together with (ROB), the Canadian Astronomical Institutes from the Belgian Royal Observatory with smaller contri- Quebec (Laval University), Montreal (University butions from the Geneva Observatory (Switzerland) of Montreal), Toronto (University of Toronto and and Landessternwarte Tautenburg (Germany). The York University), Vancouver (University of British fibre-fed spectrograph began regular science opera- Columbia), Victoria (University of Victoria), and tion in April 2009, and is designed to be optimised the Aryabatta Research Institute of Observational both in wavelength stability and in efficiency. It Science (ARIES) located in the state of Uttarak- samples the whole optical range from 380 to 900 nm hand (Northeast India). The ILMT is equipped in one shot, with a spectral resolution of 85 000 for with a 4-m rotating mercury primary mirror. It the high-resolution science fibre. The dedicated tai- has been constructed by the Belgian AMOS com- lored pipeline uses cross-correlation routines with pany and will be installed in 2018 on the Devasthal spectral templates to derive accurate radial veloc- mountain (Uttararakhand, Northern India), close ities. The long-term (5 years) radial-velocity sta- to the ARIES, located in the town of Nainital. The bility, measured from 35 IAU standard stars, is ILMT, presently under construction, has mainly 50 m/s. A better accuracy may even be achieved been funded by the Communaute Française de Bel- by using the observing mode where a wavelength- gique, the Région Wallonne, the Fonds National de la calibration spectrum is recorded simultaneously Recherche Scientifique and ULiège. The project aims with the science spectrum. A large fraction of at monitoring a narrow strip of the sky to study the HERMES/Mercator observing time (about 100 photometric and astrometric variability of celestial nights/year) is devoted to the radial-velocity moni- objects as faint as magnitude i = 22 with a time res- toring of pooled targets of different kinds, mostly olution larger than one day but over long periods of binary stars lacking orbital elements, and whose time. These observations will not only contribute to formation channel is poorly understood (sdB stars, studies of micro-lensing and of time delay measure- post-AGB stars and planetary nebulae, barium stars, ments of multiply imaged quasars but also to the ... ). A second major theme is to assemble and detection and follow-up of supernovae, of variable exploit spectroscopic information for numerous as- stars, of proper motions and trigonometric paral- teroseismic targets observed by the NASA Kepler

4http://www.aeos.ulg.ac.be/LMT/ 5http://www.mercator.iac.es

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mission. HERMES data have prompted a large num- and to the study of comets and other small bodies in ber of peer-reviewed publications, including several our solar system. It is composed of two telescopes, Nature and Science papers on asteroseismology of TRAPPIST -South, operated since 2010 at the ESO10 stars of a whole range of masses and evolution- (European Southern Observatory) - La Silla Obser- ary stages, as well as a Nature paper on the use vatory11 in Chile, and TRAPPIST-North, installed in of a thermometer and of a chronometer of stellar 2016 at the Oukaimeden Observatory in Morocco. internal nucleosynthesis of evolved low-mass stars. TRAPPIST has been highly successful in finding ex- HERMES is also used to probe the atmosphere of oplanets, resulting in several Nature papers led by evolved giant stars, through a technique known the team of M. Gillon and resulting in large atten- as tomography and developed at ULB. More re- tion in the media in 2017. Also worth mentioning is cently, the KULeuven team constructed a 3-arm fast the award of a ERC StG (SPECULOOS for Search camera MAIA6 (Mercator Advanced Imager for As- for habitable Planets EClipsing ULtra-cOOl Stars, teroseismology), which is ideally suited to study 2015-2019, PI is M. Gillon) to the ULiège team as a the pulsational characteristics of faint sub dwarf OB positive spin-off project to build new instrumenta- pulsators. This new instrument is also offered to tion with the aim to hunt for exoplanets around M the entire HERMES consortium. dwarfs. Moreover, in the same year, another ERC StG (VORTEX) was offered to O. Absil at ULiège Liège University is a junior partner of the consor- for coronagraphic studies of exoplanets. tium (consisting of University of Hamburg, Univer- sity of Guanajuato and University of Liege) that operates the 1.2 m TIGRE (Telescopio Internacional 1.2 ESO telescopes 7 de Guanajuato, Robotico-Espectroscopicot ) facility From 2006 to March 2015, and thanks to the fi- in La Luz (Mexico). This fully robotic telescope nancing by Belspo of the 4th Auxiliary Telescope HEROS is equipped with the refurbished (Heidel- of the VISA (VL TI Sub Array), Belgian astrophysi- berg Extended Range Optical Spectrograph) fiber- cists made a successful use of about 130 nights of fed echelle spectrograph, which covers the almost guaranteed time (GTO). This has led to Belgian full optical domain at a resolving power of 20 000. expertise in the very specific and demanding field The instrument is dedicated to spectroscopic stud- of interferometry, which beyond the availability of ies in stellar astrophysics. Liège University mainly the GTO is now fully exploited to request time on uses its TIGRE time to monitor early-type stars VLTI (Very Large Telescope Interferometer) and on of all spectral types (0, B, Wolf-Rayet, LBV, ... ). other instruments. Scientific results span a wide Furthermore, ULiège is currently designing a near- range of astronomical objects (pre-main sequence infrared spectrograph to be installed on the second, stars, main-sequence stars with debris discs, giant currently vacant focus of the telescope. stars with extended envelopes, post-mass transfer binaries with circumbinary discs, massive binaries The 60 em robotic TRAPPIST8 (TRAnsiting Planets ... ). Using precision near infrared CHARA (Center and PlanetesImals Small Telescope) telescope is a for High Angular Resolution Astronomy) and VL project driven by the Origins in Cosmology and As- TI interferometry, ULiège astronomers have directly trophysics group (OrCA) at the Department of As- resolved the innermost regions of the planetary sys- trophysics, Geophysics and Oceanography (AGO) tem around a main sequence star for the first time, of the ULiège, in close collaboration with the Ob- and revealed the presence of large quantities of hot servatory of Geneva (Switzerland). Mostly funded circumstellar dust within a few astronomical units by the Belgian Fund for Scientific Research9 (F.R.S.- of the bright star Vega. Their observations suggest FNRS) and the University of Liège, TRAPPIST is de- an inordinate replenishment rate, which may be voted to the detection and characterization of plan- related to a major ongoing dynamical event in the ets located outside our solar system (ie. exoplanets) planetary system. Surface brightness asymmetries 6https://fys.kuleuven.be/ster/instruments/the-maia- on the surface of AGB (Asymptotic Giant Branch) camera and supergiant stars were measured by the ULB 7https://www.gaphe.ulg.ac.be/HRT/index_e.html 8http://trappist.ulg.ac.be 10http://www.eso.org 9http://www1.frs-fnrs.be 11http://www.eso.org/sci/facilities/lasilla

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group. In the same vein R Sculptoris is being scru- from ULiège are also making the best use of Gaia tinized with PIONIER (Precision Integrated Optics DR1 (first Data Release) data to identify very com- Near-infrared Imaging ExpeRiment). This instru- pact multiply imaged quasars. ment is also used by the same group to compute astrometric orbits from interferometric data. The The Atacama Large Millimeter/submillimeter Ar- KULeuven/IvS team exploited VL TI in the topic of ray (ALMA) is a major international astronomical circumstellar and circumbinary disks of young and project. It consists of an array of 50 12m-antennas evolved stars leading to several ESO Press Releases with baselines up to 16 km, and an additional com- on this topic. Moreover, H. Sana (KULeuven/IvS) pact array of 7m and 12m antennas. Calls for pro- is currently leading an ESO Large Programme to posals have been released since 2011. Notwithstand- unravel the binarity and multiplicity of the most ing the very high over-subscription rate, Belgian massive stars in the Universe, relying heavily on proposals have been very successful during yearly VLTI. This is one of several Large Programmes from regular calls so far, with numerous peer-reviewed Belgian teams that were approved by the ESO Ob- publications including some in Nature. serving Programme Committee. Given the high pressure existing on the ESO telescope time, this The Belgian astronomical community will undoubt- remarkable achievement demonstrates the top qual- edly continue to make intensive use of ALMA in ity of astrophysical research in our country. The the coming years. This situation reflects the im- highly competitive national FWO (Fonds Weten- portant effort made by the community to gain ex- schappelijk Onderzoek) Starting Grant (Odysseus II, pertise in sub-mm and radio astronomy, a field 2016-2020) offered to Hugues Sana for his re-entry which was almost absent in the Belgian astronom- as new Professor in Astrophysics at KULeuven/IvS ical landscape until a decade ago. Many related is a direct spin-off project of his international ca- observing programmes with Belgian involvement reer and ESO Large Programme. The UGent group led to state-of-the-art publications and to a better has been leading an ESO Large Programme on the knowledge of certain categories of stars. As an internal dynamics of dwarf elliptical galaxies. The example, the teams at KULeuven, and ROB are KULeuven/IvS has been heavily involved in the probing circumstellar matter around evolved stars ESO Large Programme on ground-based support using radio observations. One particular case is the for CoRoT running from 2007 to 2012. The ROB is monitoring program of Sakurai’s object12, a famous actively involved in a public survey named VMC star that was discovered in 1996. ROB researchers (VISTA Magellanic Cloud Survey) carried-out with are monitoring its evolution on a yearly basis using the VISTA telescope in the infrared and which is the ESO- VLT telescopes, as well as ALMA to study aimed to study the star formation history of the the molecules in the circumstellar disk with the aim Magellanic Clouds. IvS/KULeuven, ROB, and ULB of deriving the isotope composition of the ejected teams (plus international partners, mostly from the material. This will enable a direct test of the theory University of Vienna) are part of the ESO Large of i-process nucleosynthesis. The UGent group has Programme entitled A joint venture in the red: the recently built up quite a strong expertise on H I Herschel+MIDI+VISIR view on mass loss from evolved studies using the 21cm line and sub-mm contin- stars, which started in 2011 and constitutes a follow- uum observations. In particular, it has been quite up of a similarly large programme carried out on successful in obtaining observing time on competi- ESA’s Herschel infrared satellite. Finally, several tive radio observatories worldwide, including the Belgian teams (ULB, ROB, ULiège and KULeuven) 4 large radio interferometers (VLA, ATCA, GMRT, are actively taking part, or even leading working WSRT) and the largest single-dish sub-mm and mm groups, of the GES (Gaia-ESO Survey), a Large telescopes. Prime examples are the involvement of Programme running over several years to provide UGent in the AGES (Arecibo Galaxy Environment spectroscopic ground-support to the currently on- going ESA’s Gaia mission. The programme aims 12A so-called "born-again" AGB star: a central star of a at providing radial velocities and abundances for planetary nebula that underwent a very late helium about 105 stars, to address the issue of the chemico- shell flash. The evolution of this star is extremely dynamical evolution of our Galaxy. Astronomers rapid and can be followed in real time, which makes it a good test case for stellar evolution models.

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Survey) project13, a survey of galaxies in different spectrograph-cum-imager FOSC (Faint Object Spec- environments with the Arecibo 305m telescope that trograph Camera, will be offered soon). These in- has been granted 2000 hours of observing time, and struments allow multi-color photometry (narrow- in the HALOGAS (Hydrogen Accretion in LOcal band and broadband filters) and low-resolution GAlaxieS) survey14, the deepest HI survey of nearby spectroscopy (R < 4000). A high-resolution spec- galaxies, that is consuming almost 3000 hours of trograph and CCD fast photometer will only be of- WSRT time. fered as second-generation instruments. The Belgo- Indian Network for Astronomy & Astrophysics The participation in radio investigations of stellar (BINA) is a network that unites Belgian and In- objects also developed at ULiège using VLA and dian partner institutes with the optimization of the GMRT (Giant Metrewave Radio Telescope), espe- scientific exploitation of the Indo-Belgian telescopes cially in the context of the study of particle accel- (4-m ILMT and 3.6-m DOT) as ultimate goal. At erating colliding-wind binaries and other galactic the Belgian side, the network is funded by BEL- non-thermal radio sources. In particular, several SPO and led by ROB. The first BINA workshop fields in the Cygnus region were observed at sev- was hosted by the Aryabhatta Research Institute of eral frequencies with the GMRT. On the other hand, Observational Sciences (ARIES) in Nainital (India) collaborations with radio astrophysicists from La on 2016, November 15-18. It attracted 107 partici- Plata (Argentina) and ASTRON/JIVE (The Nether- pants including 11 Belgian colleagues. The Royal lands) focus on the preparation of high angular Belgian Institute for Space Aeronomy (BIRA-IASB) resolution imaging campaigns using notably the deployed a network of radio receiving stations for 15 EVN (European VLBI Network). the detection of meteors, called BRAMS17 (Belgian RAdio Meteor Stations), based on the principle Last but not least in the ESO framework, the Belgian of forward scattering of radio waves from meteor astronomical community awaits the European Ex- ionization trails. A dedicated beacon located in tremely Large Telescope (E-ELT) planned for 2024. Dourbes (Southern Belgium) acts as transmitter. Al- 16 Phase B (i.e. preliminary design) studies are on- most 30 receiving stations are currently deployed going for the METIS (Mid-Infrared E-ELT Imager throughout the country, run by Belgian radio ama- and Spectrograph) instrument, with strong involve- teurs, groups of amateur astronomers, and public ments of KULeuven/IvS and ULiège (Sect. 3). observatories. In 2016, they started the citizen sci- ence project Radio Meteor Zoo in collaboration with 1.3 Others Zooniverse, involving interested people in the anal- ysis of the data. In November 2009, BELSPO signed an agreement with ARIES, on the cooperation for the construction Large Sky Area Multi-Object Fiber Spectroscopic of a 3.6m optical telescope at Devasthal ( DOT, Telescope (LAMOST) is a unique telescope located Devasthal Optical Telescope). The construction in the Xinglong Observatory (China) that combines was performed by AMOS in Liege. In return of a large aperture (3.6-4.9 m) with a wide field of this financial investment from Belspo, Belgian as- view (circular with a diameter of 5 degrees). The tronomers will receive 7% of the telescope’s observ- focal surface is covered with 4000 optical fibers con- ing time during the five first years of its operational nected to 16 multi-object optical spectrometers with life. The first call for early science with the DOT 250 optical fibers each. Hence, this instrument is was launched in March 2017. There are three first ideal to obtain low-resolution (R=1800) spectra for generation instruments: an optical CCD imager, a large number of objects simultaneously. In 2010, a near-infrared imager TIRCAM-2 (10-micron in- the LAMOST -Kepler project (PI, Peter De Cat, from frared camera, which is already available), and a ROB) was initiated with the aim to observe as many 13http://www.naic.edu/∼ages/ objects in the field of view of the Kepler space mis- 14http://www.astron.nl/halogas/ sion as possible for a homogeneous determination 15http://www.evlbi.org of stellar parameters (effective temperature, surface 16For an instrument development: Phase A denotes the gravity, metallicity, radial velocity and an estima- preliminary analysis; phase B, its definition; phase C, its design; and phase 0, its construction. 17http://brams.aeronomie.be/

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tion of the projected rotational velocity for fast rotat- proposed by BIRA-IASB, aiming at the remote sens- ing objects). The observations started in May 2011 ing of key atmospheric constituents at high vertical and in the first 4 years, about 200000 objects were resolution. The ALTIUS mission concept has been observed. studied since 2006 by BIRA-IASB, together with the OIP Sensor Systems and Qinetiq Space Belgium The Low Frequency Array ( LOFAR) is a large radio companies. After several ESA-organized reviews in telescope in the Netherlands operating in the 10-250 2015, BELSPO officially announced in early 2016 its MHz frequency range. It consists of thousands of support for the mission, end-to-end. Furthermore, omni-directional antennas and allows for multiple the ESA Earth Observation Programme Board has observation strategies. The VUB uses LOFAR to officially accepted ALTIUS as an element of the measure short radio bursts emitted by atmospheric EarthWatch programme. The road is wide open air showers from high-energy cosmic rays. The for the development of the instrument, space plat- group is funded through a highly competitive ERC form, ground segment, algorithms and launch in StG (LOFAR, Searching for the Origin of Cosmic the nearby future. Rays and Neutrinos with LOFAR, 2015-2020, PI is Stijn Buitink). In 2016, the first LOFAR results 2.2 CNES - NASA - ESA on the mass composition of cosmic rays around the galactic extragalactic transition were published astrophysics missions with in Nature. Further research is aimed at improve- Belgian involvement ment of the precision and energy range of these measurements as well as the implementation of a ROB and the Royal Meteorological Institute (RMI) new observational mode for LOFAR that allows the are involved at co-PI level in the CNES-Ied PI- search for neutrino impacts on the lunar surface. CARD mission, for the SOVAP (SOlar VAriability PICARD) instrument, a bolometer whose sensing element is based on micro-temperature differential 2 Space missions thermometers placed on a thermal shunt. BIRA- IASB also hosts its Science Operation Centre at 2.1 Belgian missions the Belgian User Support and Operation Centre (BUSOC) premises. The Belgian companies Verhaert, Spacebel and the research centre Centre Spatial de Liege (CSL) built As apparent from the above, various Belgian teams the Belgian-led Proba (PRoject for OnBoard Au- have acquired internationally recognised expertise tonomy satellites. The Proba satellites are among in the fields of solar and solar-terrestrial physics the smallest flown by ESA, yet they have a big and work often in close collaboration on joint impact in space technology. They are also part projects. On its own, each group is relatively small of ESA’s In orbit Technology Demonstration Pro- and faces various scale problems including lack gramme, missions dedicated to the demonstration of stability of technical personnel and instrument of innovative technologies. Several new technolog- scientists over time-scales exceeding that of single ical developments and scientific experiments are projects (> 3 years). To remedy this situation, the being flown on Proba satellites. Among these are Solar and Terrestrial Centre of Excellence (STCE) 18 two solar-observation experiments led by Belgian has been created at the Space Pole in Brussels. teams (from the ROB, CSL, BIRA-IASB, and the Cen- Belgian scientists (KULeuven/IvS, ULiège, ROB) tre for Plasma Astrophysics from KULeuven): the were heavily involved in the CNES-dominated Ly-alpha radiometer (LYRA), and the Sun Watcher (CoRoT mission (COnvection ROtation and plane- using APS detectors and image Processing (SWAP) tary Transits, 2006 - 2012), both at instrument level using new pixel sensor technology, taking measure- and for the scientific exploitation of the data. This ments of the solar corona in a very narrow band. expertise led to major involvement in the NASA missions Kepler and its refurbished version, K2, as Also ALTIUS (Atmospheric Limb Tracker for In- well as in the TESS mission (Transiting Exoplanet vestigation of the Upcoming Stratosphere) is part of the Proba family. ALTIUS is a satellite mission 18http://www.oma.be/index.php/en/

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Survey Satellite) to be launched in 2018. The advent The ESA infrared and submillimetre Herschel satel- of the CoRoT and Kepler space missions has consid- lite, launched in May 2009, was one of the most erably increased the potential of asteroseismology, successful achievement from ESA astronomy pro- especially for upper-main-sequence stars and red gramme. It hosted the largest mirror (3.5m) ever giant stars. Of particular interest are the slowly flown. Belgium has been involved at the co-PI level pulsating B-type stars, which oscillate in gravity (led by the KULeuven/IvS, with industrial contribu- modes penetrating deeply into the star. In those, tions from CSL, IMEC and OIP) in the design and it is possible to assess the extent of the convective construction of the Photo detector Array Camera core from the average spacing of gravity modes and and Spectrometer (PACS), one of Herschel’s three to show from the small deviations from equidis- science instruments exploring the wavelength range tant spacing that the composition gradient above 60 - 210 µm over a field of view of ∼ 1.75’ x 3.5’. the core is different from what instantaneous mix- KULeuven/IvS has opened its right of participation ing would require. Asteroseismology of red giants in the guaranteed-time programmes of Herschel to emerged when scientists from KULeuven/IvS de- all interested Belgian partners. The scientific issues tected solar-like oscillations in a red giant, which that were addressed are in the fields of star forma- resulted in a Nature paper. Here again the long and tion, mass loss of evolved stars, extreme massive precise data strings of satellites such as CoRoT en- stars with winds, nearby galaxies, high-redshift abled the detection of many non-radial modes with galaxies and cosmology. In this framework, a fairly long lifetimes. Confronting such modes with BRAIN.be project (STARLAB) was obtained in 2016 stellar-structure models for several hundred red gi- by ULB, KULeuven and ROB, providing a strong ants made it possible to clearly distinguish between incentive to collaboration on evolved stars and their hydrogen-burning (first) red giant stars and helium- environments studied with Herschel, ALMA and burning (clump) stars, and to measure the mass of HERMES. Three PhD theses in co-direction between their helium core. Moreover, KULeuven/IvS led pairs of the participating Belgian institutes are tak- a Nature paper on the first derivation of the core ing place in that context. These efforts have led to an rotation from mixed dipole modes from 2 years of impressive number of papers (co- )authored by Bel- uninterrupted Kepler data. This discovery boosted gian astronomers from various institutes. Among extensive observational and theoretical studies on them, e.g., a Nature paper on the discovery of wa- the interior rotation of evolved stars, because it was ter around carbon stars and a Science paper on found that current evolutionary models are two or- the discovery of high-redshift gravitational lenses ders of magnitude wrong in their prediction of the at submm wavelengths. This instrument activity core rotation. Much stronger coupling between core led to the involvement of KULeuven/IvS at co-PI and envelope must occur than currently predicted. level in the Mid Infrared Instrument (MIRI) con- sortium of the future James Webb Space Telescope The heritage of the Belgian CoRoT and Kepler in- (with contributions from CSL and UGent) to be volvement led to a leading role of Belgian scien- launched in 2018. The Herschel heritage also im- tists in the ESA M319 mission PLATO (PLAnetary plied involvement of KULeuven/IvS in the mission Transits and Oscillations of stars), selected in 2014 candidate ARIEL (Atmospheric Remote-sensing In- within ESA’s Cosmic Vision Programme and cur- frared Exoplanet Large-survey), currently undergo- rently in its implementation phase. KULeuven/IvS ing a design study and in competition with two and CSL lead the calibration and testing of the other mission candidates for the M4 slot in ESA’s cameras of this mission, consisting of 26 identi- Cosmic Vision programme (2015-2025). In addition, cal telescopes operating from one platform to be both KULeuven/IvS and UGent are involved in launched to L2. KULeuven/IvS and Ul.iege are the European SAFARI instrument planned for the heavily involved in the scientific exploitation of the ESA/Japanese infrared satellite SPICA (Space In- mission, both for the core programme and for the frared Telescope for Cosmology and Astrophysics), PLATO Complementary Programme, the latter led currently proposed as a candidate M5 mission. by KULeuven. PLATO will be launched in 2026. Belgian scientists playa considerable role in many of 19Third medium class mission of ESA’s Cosmic Vision the data-processing coordination units for the ESA programme (2015 - 2025) Gaia satellite (launched in December 2013), with

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ULB, ULiège, KULeuven/IvS, UAntwerpen and and 3D spatial distribution. ROB as partners (sometimes leaders) in the topics of variable stars, binaries, radial velocity determi- nation and characterisation of stars, solar-system The Advanced Telescope for High ENergy Astrophysics bodies, quasars, and gravitational lenses. The first (ATHENA) is ESA’s future X-ray telescope, under Gaia data release (DR1) took place in September development for launch around 2028. It is the sec- 2016, focused on the astrometry of single star-like ond large class mission in Cosmic Vision. ATHENA objects. ULB, ROB, ULiège and UAntwerp are cur- will be two orders of magnitude more sensitive than rently active in the preparation of the second data Chandra and XMM-Newton. The primary goals of release scheduled for April 2018 as it should con- the mission are to map hot gas structures, deter- tain the radial velocities of 5 to 8 millions of single mining their physical properties, and searching for stars, as well as astrometric binaries and solar sys- supermassive black holes. In addition, the mission tem objects, domains in which those Belgian teams will perform observations of all kinds of cosmic hold some leading positions. KULeuven/IvS made X-ray sources. The ULiège team is deeply involved the first comparison of asteroseismic versus astro- in the scientific preparation of this mission, notably metric distances of nearby dwarfs and distant red leading the Science Working Group 3.2 on Star For- giants within CU7, pointing out excellent agree- mation and Evolution. Moreover, ULiège and CSL ment and large future potential to rely on seismic contribute to the preparation of the X-IFU (X-ray distances for red giants too far away for Gaia dis- Integral Field Unit) instrument that will provide tances to become available. Another scientific issue unprecedented high-resolution X-ray spectroscopy currently addressed with the DR1 Gaia data is, e.g., of many kinds of cosmic X-ray sources. The UGent the Hertzsprung-Russell diagrams of several cate- group is also involved in the scientific preparation gories of misunderstood late-type stars (ULB and of the mission. KULeuven).

Ever since its launch in 1999,ULiège astrophysicists Since 2015, the Institute for Theoretical Physics at have been using ESA’s X-ray observatory XMM- KULeuven has developed gravitational wave sci- Newton (X-ray Multi-Mirror Mission) to study the ence as a novel research direction. It has launched X-ray emission of massive stars of all spectral types. a Centre for Gravitational Waves that acts as a plat- These studies provided unprecedented insight into form to strengthen and to coordinate nationwide the physics and hydrodynamics of stellar winds collaboration on gravitational wave science. It has and have deeply changed our understanding of also taken up a role in the gravitational wave ESA the wind interactions in massive binaries. For the mission LISA (Laser Interferometer Space Antenna) first time, XMM-Newton data unveiled the vari- which was selected for L3, the third and final large ability of the X-ray emission of single massive class mission in Cosmic Vision, earlier in 2017. LISA stars resulting from magnetically-confined stellar builds on the highly successful technology mis- winds, large-scale co-rotating wind structures, or sion LISA Pathfinder (in which Belgium was not photospheric pulsations propagating into the stel- involved). An initial phase-0 study was recently lar wind. Owing to its high sensitivity and wide completed and phase-A is scheduled to start in field of view, XMM-Newton allowed to study the April, 2018. LISA’s launch is planned for 2034. The X-ray emission of large populations of massive stars Belgian co-PI for LISA is T. Hertog who is heavily and low-mass pre-main sequence stars in various involved in the fundamental physics science goals open stellar clusters. ULiège researchers also utilize of the mission. The Belgian contribution to LISA the XMM-Newton satellite to study the cosmologi- involves also an instrumental component which cal Large Scale Structures through various interna- is being pursued in a Belgian (KULeuven/IvS) - tional consortia (XMM-Medium Deep Survey, XMM Dutch collaboration. Large Scale Structure Survey, and the XXL project). ULiège is in charge of the exploitation of the quasar aspect of the project. Detection of large numbers of In order to study the dynamics of the external layers quasars in contiguous fields, and in a homogeneous of the solar atmosphere, the ROB participates as co- manner, will enable the investigation of their 2D investigator or associated investigator in space mis-

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sions such as SOHO20/EIT21, SOHO/LASCO22, observe the rotation and orientation of Mars and STEREO23/SECCHI24. Together with ULiège/CSL, therewith to determine properties of Mars deep ROB will playa leading role in the EUI instrument interior. Sill on the same mission, ULiège (UR GE- (Extreme Ultraviolet Imaging) onboard the M1 So- OLOGY) is co-PI of the instrument named CLUPI lar Orbiter mission, to be launched in 2019. These (Close-UP Imager) and collaborator for RLS (Ra- activities complement those already described in man Laser Spectrometer) which will help to image, relation with the Proba-2 satellite (Sect. 2.1). identify, and characterize minerals.

Euclid is the M2 optical/infrared space telescope to Belgium strongly participates in the ESA corner- be launched in 2020 towards L2 (Lagrange point) stone mission BepiColombo to Mercury. ROB to- from where it will map the 3D distribution of about gether with UNamur are Co-I of three of its instru- two billion galaxies. The subsequent analysis of ments: the Mercury Orbiter Radio science Experi- the data will reveal the details of the matter dis- ment (MORE), the BepiColombo Laser Altimeter tribution throughout the Universe, including the (BELA), and the high resolution camera (SIMBIO- contribution of the dark matter. Moreover, it will SYS). Issues addressed by these instruments are the be possible to trace the accelerating expansion of rotation and interior structure and evolution of Mer- the Universe and to study the behaviour of the cury, which will be confronted to models developed enigmatic dark energy that causes the acceleration. at ROB and UNamur. UGent astronomers are deeply involved in Euclid, both in its development and its scientific exploita- ROB leads the ESA Working Group on the interior tion. The group is especially interested in studying of satellites of the JUICE (JUpiter ICy moons Ex- the ∼ 105 dwarf galaxies that will be detected. plorer) mission to Jupiter and its satellites and is co-I of five instruments: the radioscience experi- 2.3 Solar-system exploration ment 3GM (in which also UNamur is co-I), the laser missions altimeter (GALA, GAnymede Laser Altimeter), the JUICE magnetometer (J-MAG), the VIS-NIR imaging Belgium is involved in several ESA missions to spectrometer (MAJIS), and the Radio Interferometry terrestrial planets, such as Mars Express and the and Doppler Experiment (PRIDE). ExoMars missions. BIRA-IASB is PI and ROB co- I of NOMAD (Nadir and Occultation for MArs BIRA-IASB was Co-I in the ROSINA (Rosetta Or- Discovery), a 3-channel spectrometer, hosting 2 in- biter Spectrometer for Ion and Neutral Analysis) frared channels and one UV/visible channel, on the mass spectrometry consortium on the Rosetta mis- ExoMars Trace Gas Orbiter launched in 2016. The sion, which studied the physics and chemistry of infrared channels build upon the expertise of BIRA- the coma of comet 67P/Churyumov-Gerasimenko. IASB with its successful SOIR (Solar Occultation By now, ROSINA has discovered a zoo of molecules, in the Infra-Red) instrument which was onboard of which a lot have never been detected in comets ESA’s Venus Express mission. ROB was co-I of the before. This has led to a large number of high- radio science experiment of Mars Express and of the visibility publications. AMELIA (Atmospheric Mars Entry and Landing Investigation and Analysis) instrument hosted by ROB is co-I of the InSight (Interior exploration the Entry, Descent and Landing Demonstrator Module using Seismic Investigations, Geodesy, and Heat on ExoMars. ROB is also PI of LaRa (Lander Ra- Transport) mission to Mars and participating scien- dio science), the radio science experiment of the tist in the Cassini mission to Saturn and its moons ExoMars 2020 mission which has the objective to and the MAVEN (MArs Atmosphere and Volatile 20Solar and Heliospheric Observatory EvolutioN) mission to Mars. ROB exploits radio 21Extreme ultraviolet Imaging Telescope science data from many NASA missions like Mars 22Large Angle and Spectrometric Coronagraph Global Surveyor, Mars Odyssey, Mars Reconnaissance 23Solar Terrestrial Relations Observatory Orbiter, and Cassini to Saturn and its moons. 24Sun Earth Connection Coronal and Heliospheric In- vestigation

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3 Instrument design and also from a broader socio-economic and educational perspective. A strong Belgian involvement in this building project would benefit from a collaboration between the different space-instrumentation groups and the KULeuven/IvS so far took the lead in the construc- experimental high-energy physics community. tion of the HERMES and MAlA instruments for the Mercator telescope. A direct spin-off of the BIRA-IASB remains, with its Engineering Division, MAlA camera design is KULeuven’s involvement in a strong actor in the design and construction of the BlackGEM instrument, a 3-telescope instrument space science instruments. In-house prototyping to find optical counterparts of gravitational waves. is combined with outsourcing of the final produc- BlackGEM is led by the Radboud University Nijmegen. tion to industry. The division is especially skilled KULeuven designs and builds the cooling system in the design of logic systems carrying on-board for the cameras of the instrument, which will be intelligence based on microcontrollers, microproces- installed at the La Silla Observatory site of ESO end sors or Field Programmable Gate Arrays (FPGA). 2018. Although Belgian teams never were able to Associated firmware (VHDL) and software is de- take the leadership of the design and construction veloped for these platforms. The mechanical work- of a large international astronomical instrument shop is specialized in the design and manufactur- due to too limited national funds, many are directly ing of structural mechanics for space. The division involved as partners as already discussed above. has a number of facilities at its disposal for func- Current involvements in instrument development tional testing and thermal-vacuum testing. In recent concern: years, the division has successfully contributed to KULeuven and UGent for the MIRI/JWST instru- the operation of ROSINA-DFMS (ROSINA’s Double ment (currently in development Phase D); KULeu- Focusing Mass Spectrometer) on Rosetta, SPICAM ven and ULiège for METIS (currently in Phase B), (Spectroscopy for Investigation of Characteristics the Mid-infrared ELT Imager and Spectrograph for of the Atmosphere of Mars) on Mars Express and the ESO Extremely Large Telescope; KULeuven and SPICAV/SOIR (Solar Occultation at Infrared) on CSL for the instrument calibration of PLATO (Phase Venus Express, to the construction and operation of C) and for the instrument design of ARIEL (Phase NOMAD on the ExoMars Trace Gas Orbiter and of A). the Energetic Particle Telescope on Proba-V (where V stands for vegetation), and to the design of the Thanks to its expertise in high-energy astrophysics, THOR (Turbulence Heating ObserveR) Cold Solar the High-Energy Astrophysics Group from ULiège Wind instrument. together with CSL have become partners of the in- ternational instrument consortium (led by CNES) that will build the X-ray Integral Field Unit (X-IFU) 4 Synergies and resource microcalorimeter spectrograph for ESA’s next gen- pooling eration X-ray observatory ATHENA as already in- dicated above. X-IFU is an ambitious cryogenic The large effort needed in the preparation and ex- instrument that will provide unprecedented views ploitation of large missions or of complex ground- of the hot and energetic Universe. based instruments often call for the creation of large consortia. Belgian teams are indeed involved in The expertise gained in space-instrumentation by many such consortia. We list those of the past the different groups also lays the foundation for a decade here. possible Belgian contribution to the next generation of ground-based gravitational wave observatories. Within the discipline of asteroseismology, the in- Initial studies are underway to assess the feasibility stitutes involved in this kind of research in Bel- and potential to construct a third generation grav- gium (KULeuven, ROB, Ul.iege) have integrated itational wave observatory in the Dutch - German their research within the Belgian Asteroseismology - Belgian border area: the Einstein Telescope. This Group (BAG) since 2000, in the framework of pre- would constitute an exceptional opportunity for vious Interuniversity Attraction Poles. Since 2006, Belgium not only from a scientific viewpoint but Belgian asteroseismologists have opened up their

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ambition and have been integrated into European- followed by the FP7 Gaia Research for European As- funded networks rather than the BAG. The first Eu- tronomy Training (GREAT) network sponsored by ropean funded network within FP6 (6th Framework the European Science Foundation (ESF), and involv- Programme) concentrated on Helio- and Asteroseis- ing KULeuven/IvS, ULB, ROB and ULiège. mology was HELAS (European HELio- and AStero- seismology network) and ran from 2006-2010. Sub- Within the Belgian Solar-Terrestrial Centre of Excel- sequently after positive evaluations, KULeuven/IvS lence (STCE), the SIDC (Solar Influences Data anal- and Ul.iege were involved in the FP7 SpaceInn ysis Center) is a Regional Warning Centre of the project (Exploitation of Space Data for Innovative International Space Environment Service (ISES), pro- Helio- and Asteroseismology, 2012-2016) and cur- viding space weather alerts in real time or on a rently KULeuven/IvS is one of the partners in the daily, weekly or monthly schedule. It is a partner H2020 Integration Action HELAS-IA, currently in in the space weather segment of the ESA Space Stage 2 of the competition after selection in Stage 1 Situational Awareness Program. by the European Commission (success rate in Stage 2 is 1/3). ULiège chaired the European Interferome- KULeuven, ROB and ULB have jointly constructed try Initiative consortium under FP6 and FP7 the HERMES spectrograph ( for the Mercator tele- (http://www.european-interferometry.eu) aim- scope, and have agreed on a Memorandum of Un- ing at the organization of optical and infrared derstanding for its exploitation, which involves interferometry projects in Europe. more than 100 nights per year of pooled observa- tions. The largest programme on HERMES con- Finally, the study of high energy events in the cerns the atmospheric study and radial-velocity universe as supernova, active galactic nuclei and monitoring of a large and diverse sample of binaries gamma ray bursts make use of a multi-messenger with late-type components. This programme and approach combining astronomical measurements most of the other projects that ran or are request- and the detection of high energy cosmic rays, pho- ing data from the instrument are collaborations tons and neutrinos. These multidisciplinary activi- between the member institutes of the HERMES con- ties are described in the "Research activities in fun- sortium. damental interactions, from particles to cosmology, in Belgium". Various international consortia (XMM-Medium Deep Survey, XMM Large Scale Structure Survey, and the XXL project) were mentioned in relation 5 Theoretical astrophysics with the ULiège activities in XMM-Newton. Liège research in Belgium University was also involved in the international Chandra Cygnus OB2 Legacy Survey (study of the Nuclear astrophysics is a traditional niche of ULB X-ray emission of massive stars in Cyg OB2) and a theoretical research, with the computation and com- large multi-wavelength campaign to study the near- pilation of nuclear data of astrophysical interest25,26 , est massive eclipsing binary δ Ori, notably with including the equation of state of dense matter in four deep Chandra exposures. extreme astrophysical environments such as neu- tron stars. The group has a strong expertise in the The European Leadership in Space Astrometry s-, r- and p- processes of nucleosynthesis, studied (ELSA) was a Marie Curie Research Training Net- through parametric approaches or through uni- or work supported by the European Community’s multi- dimensional stellar evolution models. The- Sixth Framework Programme (FP6), which started oretical research at ULB involves as well stellar in October 2006, lasted for 4 years, and involved evolution covering all evolutionary stages27 from ULB. The overall objectives of ELSA were to de- pre-main sequence to neon combustion for a vast velop the theoretical understanding and practical mass range, with new developments regarding the analysis tools of importance for the European Space Agency’s astrometric mission Gaia and to foster the 25http://www.astro.ulb.ac.be/bruslib/ development of a new generation of researchers 26http://www.astro.ulb.ac.be/Netgen/form.html in the area of space astrometry. ELSA has been 27http://www.astro.ulb.ac.be/-siess/Site/STAREVOL

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binary evolution (BINSTAR code) and rotationally- package of the new Intel Exascience Lab32 is on space induced mixing, using hydrodynamical tools when weather modelling, with KULeuven/CmPA acting needed, and treating the associated nucleosynthe- as coordinator, where 5 Flemish universities, IMEC sis. The developments about BINSTAR are done in and Intel collaborate in work packages. Relativis- collaboration with VUB, which has a long-standing tic gas and plasma modelling for Active Galac- research history in this field. 3D hydrodynamical tic Nuclei jets and in the extreme conditions of models of supergiant atmospheres are also com- Gamma Ray Bursts is done in close collaboration puted, and confrontations are performed with abun- with Utrecht and Amsterdam colleagues, as part of dances derived from observations. Moreover, ULB the COST action MP0905. The CmPA was recently is involved in the modelling of neutron stars, their awarded an ERC Consolidator grant (BOSS-WAVES, internal constitution and their hydrodynamics espe- 2018-2022, PI is T. Van Doorsselaere) for the study cially superfluidity. ULB is a partner of the COST of backreaction of the solar plasma to waves. action MP130428 NewCompStar: Exploring funda- mental physics with compact stars. The Atomic Physics and Astrophysics Group of Mons University has a long-standing tradition in the de- A strong theoretical expertise exists in Belgium termination of fundamental parameters, such as (ULiège, KULeuven/IvS) regarding theoretical com- radiative and collisional rates, for atoms and ions of putations of the nonradial oscillation spectra of var- astrophysical interest, particularly for the investiga- ious kinds of stars in the context of asteroseismol- tion of the chemical composition of stars (including ogy. In particular, thanks to the highly competitive the Sun and the chemically-peculiar stars) and the ERC Advanced Grant team led by KULeuven/IvS analysis of stellar nucleosynthesis. For that pur- (MAMSIE, Mixing and Angular Momentum tranS- pose, elaborated theoretical approaches and up-to- port of massIvE stars, 2016-2020, PI is C.Aerts), date experimental techniques (time-resolved laser- asteroseismology is now getting bridged with 3- induced fluorescence spectroscopy, Fourier trans- dimensional hydrodynamical simulations to build form spectroscopy ... ) are currently used. In addi- new theoretical stellar evolution models of massive tion, several unique databases, storing atomic data stars calibrated by gravity-mode oscillations. for heavy elements (5th, 6th rows of the periodic table, lanthanides, actinides), have been developed The Centre for mathematical Plasma-Astrophysics containing position and intensity parameters for a at KULeuven (KULeuven/CmPA) focuses on the- large number (over 100 000) of transitions belonging oretical and computational plasma physics, rele- to ions of astrophysical interest (DREAM (Database vant for solar physics, astrophysics and labora- on Rare-Earths at Mons)33 and DESIRE (DatabasE tory (fusion) plasmas. Key applications include on Sixth Row Elements)34 ) and of interest for laser magneto-seismology in the solar corona, all as- devices and for fusion research (ADAS, Atomic pects of space weather, relativistic plasma dynam- Data and Analysis Structure, collaboration). A new ics, and fundamental plasma physics research. project is currently also dedicated to the study of KULeuven/CmP A coordinates several ongoing plasma environment on the atomic structure and EC-FP7 and H2020 projects targeting space weather processes involving K-vacancy states for different applications, namely Soteria29 (SOlar TERrestrial ionic systems in the context of high-density astro- Investigations and Archives) and SWIFF30(Space physical media such as accretion disks around black Weather Integrated Forecasting Framework) as well holes. as SOLSPANET (Solar and Space Weather Network of Excellence). It is involved in European Research KULeuven (IvS, Department of Chemistry, Depart- and Training Networks (specifically SOLAIRE31. The ment of Mathematics) has been granted an Inter- group does a lot of numerical work, targeted to disciplinary Research Project (IDO) to develop a high performance computing, since the prime work 32http://www.exascience.com 28http://www.cost.eu/COST_Actions/mpns/MP1304 33http://hosting.umons.ac.be/html/agif/databases/ 29http://soteria-space.eu/ dream.htmI 30http://www.swiff.eu 34http://hosting.umons.ac.be/html/agif/databases/ 31http://www.iac.es/solaire desire.html

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multidimensional theoretical code for exoplanet at- stability zones - candidates for parking orbits or mospheres, including radiative transfer, chemistry, zones of accumulation of debris - and the analysis dynamics, cloud formation etc. Expertise on the of the solar radiation pressure for specific debris. similar topic of non-LTE radiative transfer in dusty NaXys has developed a full expertise in theoret- circumstellar shells around evolved stars is already ical cosmology as well, focusing on dark energy, existing in the KULeuvenlIvS team, thanks to the simulations of cosmic structure formation with nu- code GASTRoNOoM coupled to a dust radiative merical relativity techniques, alternative theories of transfer code (MCMAX). This KULeuvenlIvS team gravitation and the derivation of multi-scale com- recently got a large boost thanks to the award of an bined constraints (solar-system, Hubble diagram, ERC Consolidator grant (AEROSOL, 2016-2020, PI compact objects, CMB37 and large-scale structure is L.Decin). physics). The NaXys group is member of the Euclid Consortium. The group is involved into tests of The ROB has been granted a BRAIN.be Network- general relativity and inflationary scenarios with ing Project for the development of the Belgian Euclid, which requires careful modeling of observ- Repository of Atomic data and Stellar Spectra by ables. The cosmology group in NaXys has recently the Belgian Federal Science Policy Office (BRASS, opened a new line of research in electromagnetic 2014-2018, PI is A.Lobel). The Project is a scien- detectors of gravitational waves, which are comple- tific collaboration on astrophysics research of the mentary to current laser interferometers since they ROB, KULeuven, European Southern Observatory will allow probing higher frequency ranges (kHz to at Paranal (Chile) and ULB. The follow-up commit- THz and higher). tee also involves the University of Antwerp and The UGent astronomy group focuses on the the Vereniging voor Sterrenkunde in the project. kinematics and dynamics of galaxies, including BRASS (Belgian Repository of fundamental Atomic their formation, evolution, and structure,especially Data and Stellar Spectra) also involves a PhD pro- for dwarf galaxies, through state-of-the-art N- gram to be completed at the KULeuven. BRASS body/SPH simulations. This research is backed by takes a first, but crucial, step towards removing observational collaborations and will have strong all systematic errors in atomic input data required ties with the data coming from the future ESA Eu- for quantitative stellar spectroscopy. It will thor- clid mission. A second major theoretical topic is oughly assess the quality of fundamental atomic the study of the interaction of matter and radia- data available in the largest repositories by com- tion through radiative transfer 3D, non-LTE simu- paring very high-quality observed stellar spectra lations. These radiative transfer techniques have with state-of-the-art theoretical spectra. Whereas led to the development of a radiative transfer code this type of study has currently been carried out that is mainly used to model the dusty interstellar for very few stars at the time, and mostly limited to medium in galaxies, in particular to analyze far- comparable spectral types assembled from various infrared observations of nearby galaxies, such as sources, BRASS will combine, analyze, and offer those obtained by Herschel (Sect. 2.2). Finally, the the community the first uniform large collection of topic of galaxy dynamics has also developed into benchmark and reference stars35,36 This study will the investigation of dark matter halos and modified be more complete than any other to date in terms gravity: the UGent group is using mainly radio of coverage of the stellar parameter space, as well observations to determine the mass distribution in as the spectral wavelength coverage. galaxies and interpreting these using either models for dark matter or alternative gravity theories. NaXys (Namur Centre on Complex Systems) at UN- amur has recently applied its long-standing exper- The ROB involvement in many solar-system explo- tise in celestial mechanics and Hamiltonian theory ration missions goes along with the modelling of to exoplanets (high mutual inclinations, Kozai reso- the interior structure and dynamics of terrestrial nance and migration) or to artificial satellites and planets and moons of the solar system, building on space-debris dynamics (in particular the search for the expertise developed from the 1960s on the rota- tion of the Earth. New methods are developed to 35http://brass.sdf.org 36 37Cosmic Microwave Background

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investigate the deep interior structure as well as the goal is to understand the volatile composition and crust and lithosphere. A particular focus is on the the isotopic composition and to explain how these study of the rotation, gravity field, and tides. Earth can be traced back to the properties of dense molec- rotation theoretical studies are presently on-going ular clouds or processes that occurred during solar thanks to a ERC AdG grant financing the project system formation and subsequent evolution. The ROTANUT (Rotation and nutation of a wobbly emphasis is on gas-grain interactions and the asso- Earth, PI is V. Dehant) whose objective is to better ciated chemistry. This work is carried out in close understand the fluid core contributions to the vari- collaboration with the ULB’s research group on ations of the Earth orientation in space (so-called Quantum Chemistry and Photophysics. nutations). Historically, one of the first tasks of ROB was to build star catalogues and to contribute to the Within ULiège (UR GEOLOGY), the StG ERC ELiTE determination of the Universal Time from meridian (PI is E. Javaux) focus on the study of Early Life observations. In the 1970s, the ROB followed the Traces and Evolution, and Implications for Astrobiology. transition to atomic time, with the installation of Astrobiology studies the origin, evolution and dis- atomic clocks and their integration in the world net- tribution of life in the Universe, starting with life work used for the realization of the UTC. The ROB on Earth, the only biological planet known so far. also provides a local representation of UTC avail- The project ELiTE consists on identifying the early able in real time. Current research is performed on traces of life and their preservation conditions, char- time transfer (i.e. remote atomic clock comparisons) acterizing their biological affinities, determining methods and strategies. The ROB is coordinating the timing, pattern and causes (biological, environ- the EUREF Permanent Network38 (EPN) with a par- mental) of major steps in evolution, in particular ticular emphasis on the study and mitigation of the rise of biological complexity (the evolution of error sources degrading the positions and velocities cyanobacteria and the domain Eucarya). Astrobio- of Global Navigation Satellite System stations. The logical implications include refining criteria for the Astronomy and Astrophysics department provides detection of unambiguous extraterrestrial biosigna- public access to atomic data to assist spectroscopists tures. The project aims therefore to investigate the in the identification of atomic lines in astrophysical early traces and diversification of life and the chang- or laboratory spectra. It is widely used in the as- ing habitability conditions of Earth that sustained tronomical and physical community. It is involved life, from its earliest traces in the Archean through in the development of the open source photoioniza- the Proterozoic. These studies are improving the tion/PDR spectral synthesis code Cloudy, which is characterization of (1) biosignatures and analytical the only interstellar medium modelling tool that can protocols useful for paleobiology and exobiology produce a self-consistent model of a photo ionized missions (e.g. as co-PI of instrument CLUPI and region including the PDR and molecular regions collaborator for RLS on ExoMars 2020); and of (2) surrounding it. Research in the department further interactions between the biosphere, the geosphere, focuses on visual and spectroscopic multiple stars and the atmosphere through time. These last two (especially spectral disentangling), pulsating stars, points are also the focus of the lAP PLANET TOP- central stars of planetary nebulae, and hot stars ERS39 (Planets: Tracing the Origin, Preservation, Evolu- (stellar winds, rotation, etc.). tion of their Reservoirs, PI: V. Dehant at ROB; co-PI: E. Javaux at ULiège, V. Debaille at ULB, A.C. Vandaele Not yet mentioned previously for ULiège are vari- at BIRA-IASB, P. Claeys at VUB, F. Vanhaecke at ous theoretical studies on astroparticles, e.g., show- UGent, T. Spohn at DLR Germany). ing that the constraints on circular polarisation rule out axion-photon mixing as the explanation of the Gravitational wave astrophysics is another branch systematic alignment of the polarisation of light of astrophysics in development in Belgium. The from quasars, and intensive gravitational lens mod- gravitational waves centre40 (KULeuven, ULB, UCL elling. and VUB) is a recent initiative focussed on the theo- BIRA-IASB’s Space Physics division has developed retical study of gravitational waves. KULeuven and expertise on comets in the frame of Rosetta. The 39http://iuap-planet-topers.oma.be/ 38http://epncb.oma.be/ 40https://fys.kuleuven.be/gwc

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ULB are part of the COST (European Co-operation and gravitational wave observations. It is supported in Science & Technology) action CA16104 Gravi- in part by the ERC CoG HoloQosmos. tational waves, black holes and fundamental physics through T. Hertog and G. Compère. Gravitational The Service de Physique Théorique at ULB and the CP3 wave source modelling is currently in development at UCL have a long-term activity on the physics at for extreme mass ratio inspiral and merger events, the interplay between particle physics and physics supported by the ERC StG HoloBHC (PI: G. Com- of the Early universe. This includes mechanisms père) and ERC CoG HoloQosmos (PI: T. Hertog). of baryogenesis and leptogenesis to explain the Fundamental physics signatures are also under de- emergence of the asymmetry between matter and velopment at KULeuven (B. Vercnocke). antimatter of the universe, models of dark matter (WIMPs, axions, primordial black holes), phase tran- sitions in the Early universe associated to the break- 6 Cosmology ing of local and global symmetry, the role of neutri- nos in cosmology and in astrophysics, mechanisms 6.1 Cosmochemistry of inflation, including the generation of primordial inhomogeneities and their evolution, physics of the Cosmochemistry uses the chemical composrtion CMB and of the dark age, etc. The activities at (elemental and isotopic) of meteorites to date and ULB also include the field of cosmic rays (including investigate the condensation of the solar nebula, neutrinos, positrons, antiprotons and gamma-rays) including the possible late injection of stellar ma- and ultra-high energy cosmic rays, in particular the terial, the accretion of dust newly condensed with study of anisotropies (member of the Telescope Ar- presolar grains, the formation and differentiation ray collaboration) and the modelling of the galactic of asteroids, and planetary evolution. The Labora- and extragalactic magnetic fields. toire G-Time at ULB (V. Debaille) and the AMGC at VUB (Analytical, Environmental and Geo- Chem- istry, S. Goderis and P. Claeys) collaborate on this topic through several BELSPO projects and the lAP PLANET TOPERS. An ERC StG (ISoSyC) on the topic has also been granted to V. Debaille (2014- 2019). To obtain meteorite and micrometeorites samples,?several field campaigns have been orga- nized in Antarctica, and more than 1000 meteorites are now present in the Belgian Antarctic collection at the Royal Belgian Institute for Natural Sciences. State-of-the-art analytical facilities, including sev- eral multi-collection-inductively coupled plasma- mass spectrometers, at ULB, VUB and UGent are used for performing high-precision isotope analy- ses.

6.2 Early Universe

Since 2011 the Institute for Theoretical Physics (ITF) at KULeuven has pursued an active research pro- gram in early universe cosmology. This includes the study of inflation in the early universe, its em- bedding in quantum gravity based models of the big bang and its possible observational signatures most notably in the form of (very long wavelength) gravitational waves. As such this program serves as a bridge between fundamental high-energy physics

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Research Activities in Plasma Physics in Belgium

R. Weynants

Department of Physics, Royal Military Academy 30 Avenue de la Renaissance/Renaissancelaan, 1000 Brussels

1Plasma physics research in Belgium is tradition- tempt is therefore made to draw a border between ally organised along three main lines: astrophysical physics, chemistry and technology of material de- plasmas, hot or fusion plasmas and cold plasmas or velopment. An important sub-area here is plasma gas discharge technology plasmas. This text gives a surface interaction for which an Interuniversity At- concise and therefore non-exhaustive review of the traction Pole (lAP) exists since 2007. activities in these three areas at the Belgian univer- A last preliminary remark concerns the relative new- sities and research institutions. comer in this research field that is the dusty plasma. An important part of this work is taking place in Dust grains can be immersed in ambient plasma, be- the context of national or international cooperation, come electrically charged and can thereby give rise thus providing a lot of leverage to the relatively to new, sometimes intriguing phenomena. Dusty small groups that are involved. As such, the astro- plasmas are intensively studied by space physicists physical effort draws strength from collaborations in this country, but also by the gas discharge plasma within Horizon 2020 projects [1] such as SOTERIA, community. SPACECAST, SOLSPANET, SWIFF and eHEROES, and the Virtual Space Weather Modelling Centre Consortium (VSWMC) [2] within the framework of 1 Astrophysics the European Space Agency (ESA). Hot plasmas, on the other hand, are mostly studied in the con- Most of the Belgian plasma effort in astrophysics text of thermonuclear fusion research by means of concentrates on the phenomena occurring in the magnetic confinement. Since 2014 this Europe wide Sun and on the interaction of the solar wind with activity is no longer taking place in the framework the heliosphere and the earth magneto- and iono- of an Association with EURATOM but within the sphere and its role as driver of Space Weather. context of the Consortium for the Development of Of particular importance in recent years has been Fusion Energy EUROfusion [3]. the collaboration within the context of the ESA or Please note that in the area of plasma technology EU projects mentioned earlier, but also within the a lot of activities are multi-disciplinary and no at- CHARM IAP P7/08 network on contemporary as- trophysical and heliospheric modelling, involving the Centre for mathematical Plasma Astrophysics 1The Belgian National Committee for Pure and Ap- plied Physics (BNCPAP) is responsible for the con- [4] at KU Leuven, the Astronomical Observatory tent of the present review article. For any re- [5] at UGent, the Fluid and Plasma Dynamics Re- mark please contact the secretary of the BNCPAP search Unit [6] at ULB, the Solar Physics Research ([email protected]). Department of the Royal Observatory of Belgium

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[7] and the Solar Wind Research Unit of the Belgian observations and state-of-the-art numerical simula- Institute for Space Aeronomy [8], together with tions, and is involved in the development of instru- groups at Leiden (NL) and Durham (UK). The work mentation for several new telescopes. packages included: ULB-Fluid and Plasma Dynamics [6] studies the • the coupling of existing tools (software and dynamics of conductive flows and specialises in the numerical solvers) and models (PDE mod- numerical simulation of hydrodynamic turbulence. els/particle treatments/radiative effects) to- Direct numerical simulations are complemented by wards more realistic multi-physics descrip- large eddy simulations, based on the application of tions, a spatial filter to the Navier-Stokes equation.

• the confrontation of model predictions with The SIDC at ROB [7] monitors solar activity in the vastly increased armada of space instru- many wavelength bands, using advanced imaging ments monitoring the Sun and the heliosphere, techniques, and provides high-level space weather reports and solar activity predictions to industry • the role of turbulence in particle acceleration and to the wider community. on astrophysical plasmas,

• the multi-scale description by correlating IASB/BIRA [8] extensively studies the solar wind MHD and kinetic models, properties from satellite data (CLUSTER satellites) and models them by kinetic plasma descriptions. • the role of radiation on the dynamics in gases The Energetic Particle Telescope (EPT), designed by and plasmas. the laboratory in collaboration with the Centre for Space Radiations at UCLouvain [9] and placed on These efforts are further assisted and reinforced by board the Belgian satellite PROBA- V, is providing specific research topics of the individual groups. important information on the generation and loss As such, CmPA/KULeuven [4] concentrates its re- processes associated with the Van Allen radiation search on the dynamical interaction between plas- belts. An extensive database on the conditions pre- mas and magnetic fields covering hereby a wide vailing on Comet 67P/G-G and obtained by the range of phenomena such as many aspects of our Rosetta spacecraft was also gathered. local space weather, where magnetic activity in the solar atmosphere controls the appearance of waves, instabilities, flows, shocks, heating, and the acceler- 2 Fusion Plasmas ation of the solar plasma into our heliosphere. Also covered are planetary and stellar magnetospheric The Laboratory for Plasma Physics of ERM/KMS physics, the turbulent motions in accretion disks or (LPP-ERM/KMS) [10] is the implementing agent of the relativistic jets emerging from entire galaxies. EUROfusion in Belgium. Theoretical and experi- CmPA/KULeuven has also a significant effort on mental aspects of heating and confinement of fusion the numerical modelling of plasmas, from kinetic plasmas are the main focal points of its activities. to fluid descriptions, going from non-relativistic to The preferred heating method is that which seeks relativistic flow regimes. The latter are particularly to make electromagnetic waves interact with the important for the study of jetted outflows (Active cyclotron motion of the plasma ions. To this end, Galactic Nuclei jets, Gamma Ray Bursts, ... ). Effects refined modelling codes are developed permitting of dust grains in rotating self-gravitating plasmas the optimised launching, propagation and absorp- are also studied. tion of the appropriate waves. A spin-off of these studies is the design of high-power wave launching The research of the UGent-Astronomical Observa- and heating systems for fusion machines. As such, tory [5] concentrates on understanding the struc- the design, construction and testing of a new "ITER- ture, origin and evolution of galaxies, with a particu- like antenna" on JET (the Joint European Torus) has lar focus on dwarf galaxies, galaxy dynamics and in- led to proposal of a high power density launcher terstellar dust (as a core team of the EU FP7-project (∼10 MW/m2) which was adopted by and is now DustPedia). The team uses both multi-wavelength implemented for ITER (the International Tokamak

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Experimental Reactor). The confinement of fusion all microscopic processes. Optimisation of magnetic plasmas relies heavily on the thermal insulation control for power exhaust in divertor Tokamak re- provided by the plasma edge properties. The effect actors is also studied. of edge turbulence, possible tailored by the use of radial electric fields or of plasma seeding by edge Experimental work is performed at UCLouvain radiating impurities on the thermal insulation is (NAPS [14]) to provide absolute cross-sections for a further research topic of this group. Note that many elemental atomic or molecular reactions oc- appropriate diagnostic means are developed where curring in the edge of fusion plasmas, or to calibrate needed. some of the particle beams that are used as diag- nostic tools for many fusion plasma parameters. The Belgian Nuclear Research Centre SCK•CEN [11], provides the Belgian technology input to EU- The kinetic and the fluid description of fusion plas- ROfusion. Although not related directly to plasma mas, including magnetohydrodynamic effects, heat- physics, these studies form a crucial element in ing and neoclassical transport theories is actively the justification of the energy orientation of fusion studied at ULB-Fluid and Plasma Dynamics [6]. plasmas. Of particular importance is the testing of first wall and structural reactor materials under At CPA/KULeuven [4], several software tools have neutron bombardment. A multi annual irradiation been developed and applied to diagnose tokamak campaign of innovative new tungsten alloys un- equilibria (for both static and stationary, rotating ax- der High Temperature High Flux conditions in BR2 isymmetric configurations), and accurately quantify started in 2017. Radiation hardened microelectron- all MHD wave modes, important for active and pas- ics for diagnostics and remote handling units, un- sive MHD spectroscopy and instabilities occurring der development with an industrial partner. and a in fusion plasmas. novel plasma current sensor based on birefringence in optical fibre are other recent research projects. Recently sensors to measure the local magnetic field 3 Plasma technology in ITER during operation were successfully tested for neutron exposure. The last few decades have seen an exponential de- velopment in industrial applications of cold plas- At the Department of Applied Physics of UGent, mas for such diverse purposes as material process- the research unit Nuclear Fusion [12] develops ing, etching and coating, plasma light sources and novel techniques for the real-time analysis of fusion displays, decontamination and detoxification, envi- plasma signals and images, as well as data mining ronmental and medical applications, etc .. Several techniques for massive fusion databases (disrup- Belgian groups contribute to the plasma physical tions, scaling laws), using a probabilistic approach. understanding of this area of plasma technology The study of the physics, the technology and the and to the initiation of yet further applications. processes accompanying the application of plasma heating using the ion cyclotron range of frequency Several activities in plasma surface interaction are method is another core research area, pursued in currently taking place in the context of Interuni- close collaboration with LPP-ERM/KMS and the versity Attraction Pole (lAP) Project P7/34 on the MPI for Plasma Physics in Munchen (D). Ghent Uni- Physical Chemistry of Plasma-Surface Interaction versity is the coordinator of the Erasmus Mundus (PSI) [15]. The partners in this endeavour are ULB ’International Doctoral College in Fusion Science (4MAT [16], CHANI Plasma [17], UAntwerpen and Engineering’ and of the Erasmus Mundus ’Eu- (PLASMANT [18]), UCLouvain (BSMA, Polymer ropean Master in Nuclear Fusion Science and Engi- coating group [19]), UMons (Chemistry Department neering Physics’ [20]), as well as groups from Toulouse and Eind- hoven. This project merges the expertise of the At the KULeuven, Department of Mechanical En- research units in plasma diagnostics (optical, elec- gineering [13], the neutral particle transport in the trical probe, laser induced fluorescence and mass plasma edge is modelled with a Monte Carlo simu- spectrometry techniques), in the fundamental study lation of the kinetic equation, taking into account of the ionized gas phase and its hydrodynamics, in

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bulk plasma and plasma-surface interaction mod- discharge sources at reduced pressure are exten- elling (molecular dynamics, Monte Carlo) and in sively studied and modelled to extend their deploy- (organic and inorganic) material synthesis, func- ment. A number of simulation techniques are also tiona1ization and characterization using state-of- developed in the realm of accelerated molecular the-too1s. The specific contributions of the partici- dynamics (MD) and enhanced sampling, in particu- pant groups are appearing below. lar force bias Monte Carlo (fbMC) simulations and collective variable-driven hyperdynamics (CVHD) At ULB, the 4 MAT group [16] performs experimen- simulations. tal and modelling investigations of plasma-catalysis At the Department of Applied Physics of UGent, for CO or CO /H O dissociation. A further activ- 2 2 2 the research unit Plasma Technology [21] uses non- ity deals with select different materials or coatings thermal plasmas for the abatement of volatile or- capable of meeting the stringent mechanical and ganic compounds in waste gas streams and for bio- economical requirements of Micro CHP Applica- material treatment, such as the treatment of porous tions (ECOJET). The CHANI Plasma Team [17] tai- scaffolds and biodegradable polymers and cleaning lors surfaces by atmospheric plasmas: deposition of metallic surfaces used for implants. A number of of organic, inorganic, metal and hybrid nano-layers. plasma sources at medium or atmospheric pressure Important projects are: Transformation and val- are further used for the treatment of polymer films orization of CO ; synthesis and grafting of nanopar- 2 and textiles. The Plasma Physics and Engineering ticles to develop catalysts (including for fuel cells) group [22] has three main lines of investigation and sensors; degradation of COV by atmospheric (i) absolute density measurements of active species plasma process; synthesis of fluorinated membranes (OH, O, O3, Arm) in cold plasmas by means of laser for fuel cell applications; study of water reactivity spectroscopy, (ii) the development of novel atmo- at a plasma/polymer interface. spheric pressure plasma sources for applications in surface engineering, biomedical and environmental The BSMA Polymer coating group of UCLouvain technology, (iii) plasma generation and dynamics [18]), focuses on the understanding of the structure in bubbles, plasma-liquid interactions and radical and the local chemistry of polymers synthesized or production in connection to material and waste treated in (almost) atmospheric pressure plasmas. treatment applications.

At UNamur, the Laboratoire interdisciplinaire The Chemistry of Plasma Surface Interactions de spectroscopie électronique (LISE) [23] applies Unit of UMons [19] studies the conversion of pol- plasma treatment techniques (cleaning, coating, luting gases, synthesizes nano-objects and deposits functionalization) to a variety of materials such thin layers by means of Physical vapour deposi- as nanotubes, fullerene, graphene, ceramics, poly- tion (PVD) and Plasma-enhanced chemical vapour mers and biomaterials and investigates their surface deposition (PECVD). properties.

At UAntwerpen, the PLASMANT research group VITO, the Flemish institute for technological re- [20] covers a broad spectrum of plasma applications. search [24], currently focuses on cold plasma tech- It aims at plasma-based optimisation of CO2 con- nology at atmospheric pressure for a broad range version into value-added chemicals and renewable of surface treatment applications. Applications in- fuels and of nitrogen fixation. In plasma medicine, clude the control of adhesion or release properties, the potentiality of the reactive species in plasma jets biofunctiona1, anti-bacterial and low friction coat- for bacterial killing and cancer treatment is strongly ings, etc. Moreover, plasma enhanced catalysis is pursued. Recent focal points in the domain of mi- studied to convert greenhouse gases into useful croelectronics and nanotechnology are cryogenic chemical precursors. VITO has developed several plasma etching, modelling of the growth of car- atmospheric plasma systems for specific surface bon nanotubes and the design and development functiona1ization: in 2017, the spin-off Apemco of nanocatalysts and nanoclusters. With an eye was founded, which builds and maintains plasma- on analytic chemistry, inductively coupled plasma machines based on VITO’s know-how. More infor- sources operating at atmospheric pressure or glow mation can be found on www.apemco.eu.

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At IMO, the Institute for Materials Research, [6] http://aqua.ulb.ac.be/home/ UHasselt [25], a number of plasma techniques are used for the deposition and synthesis of materials, [7] http://www.sidc.be/ such as UHV plasma etching, reactive ion etching [8] http://www.aeronomie.be/ and microwave plasma-enhanced CVD. With the lat- ter, a wide variety of diamond layers can be grown [9] http://web.csr.ucl.ac.be/uclelicsr/ on several substrates, possessing unique properties [10] http://fusion.rma.ac.be/ for advanced applications, such as dye sensitized solar cells or diamond UV -detectors. [11] http://www.sckcen.be/en/Technology_future/ Nuclear_fusion Het Interuniversitair Micro-Elektronica Centrum (IMEC) [26] studies plasma etching by means of [12] https://www.ugent.be/ea/appliedphysics/en/ inductively-coupled plasma (ICP) or RF capacitively research/fusion coupled sources (RFCCP) or by high-density plasma [13] https://www.mech.kuleuven.be/en/tme/research/ chemical vapour deposition (HDPCVD). Methods thermal/home are developed on how to cope with the continuous downscaling of integrated circuit and the use of new [14] https://uclouvain.be/en/research- materials. Recent lines of investigation are damage institutes/imcn/naps prevention, such as by the use of low energy and low fluence, or cryogenic precursor condensation [15] https://www.belspo.be/belspo/fedra/proj.asp?l=en while etching porous substrates. &COD=P7%2F34

A research group at the Von Karman Institute (VKI) [16] http://4mat.ulb.ac.be/ [27] works on the synthesis of metallic and ceramic [17] http://chani.ulb.ac.be/research.php?part=B nanoparticles by means of radio frequency (RF) ther- mal plasma processes. The research activities are [18] https://uclouvain.be/en/research- mainly focused on the development and validation institutes/imcn/bsma of mathematical models of the plasma reactor and [19] https://portail.umons.ac.be/en2/universite/facultes/ of nanoparticle formation (generation and growth). fs/services/institut_chimie/chimie_interactions_ VKI also develops small scale plasma sources (Min- plasma-surface/pages/default.aspx itorch and MPT) based on RF and microwave to generate subsonic and supersonic plasma flow un- [20] https://www.uantwerpen.be/en/rg/plasmant/ der situations representative of high speed atmo- spheric entry conditions, also studied on the PLAS- [21] https://www.ugent.be/ea/appliedphysics/en/ MATRON device, the world largest inductively cou- research/plasma/plasmatechnology.htm pled plasma torch. [22] https://www.ugent.be/ea/appliedphysics/en/ research/plasma/plasmaphysicsandengineering.htm

[23] http://www.unamur.be/sciences/physique/lise References [24] https://plasma.vito.be/en

[1] http://cordis.europa.eu/programme/rcn/ [25] http://www.uhasselt.be/IMO 863_en.html [26] https://www.researchgate.net/institution/imec/ [2] https://esa-vswmc.eu/ department/Plasma_Etching

[3] https://www.euro-fusion.org/ [27] https://www.vki.ac.be/

[4] http://wis.kuleuven.be/cpa/

[5] http://www.ugent.be/we/physics- astronomy/en/research/astronomy/

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Research Activities in Computational Physics in Belgium

Xavier Gonze and Gian-Marco Rignanese

IMCN/NAPS, Universite´ Catholique de Louvain, 8, chemin des etoiles´ L07.03.01, B-1348 Louvain-la-Neuve

1Computational physics (CP) is in first instance the wide range of problems from quantum mechanical study and implementation of numerical and sym- calculations to highly complex data processing and bolic models and algorithms for the simulation of it is not always easy to pinpoint specific research in physical systems, based on an existing quantitative the field. New developments appear mostly as by- theory. CP is maturing as the third leg of the sci- products of other researches made in different fields entific enterprise alongside with experiment and by groups that rely on computers to perform their theory. Computer performance that evolves at an works. This inventory of the Belgian contributions exponential rate allows new ways of apprehending in CP will thus collect works made by physicists and solving problems. We are now able to inves- that are heavily involved m developing and improv- tigate computationally fundamental questions in ing computer codes and architecture in order to physics with unprecedented fidelity and level of de- perform their research. tail. And that trend will surely continue for many years. For convenience, the following global structure for the present inventory2 was chosen: However, CP implies more than using simulation to provide insight and interpretation. The IUAP com- mission on computational physics [1] has broad- 1. Numerical and symbolic models and algo- ened the field to include the computational control rithms for the simulation of physical systems. and data processing of experiments, programming and computational environments, and the physi- 2. Computational control and data processing of cal basis of computer machinery. Thus, CP also experiments involves the acquisition and management of seas of experimental data (as in high-energy physics) and 3. Programming and computational environ- new techniques of data acquisition and handling. ments

As a result, computational physics covers a very 4. The physical basis of computer machinery. 1The Belgian National Committee for Pure and Ap- plied Physics (BNCPAP) is responsible for the con- tent of the present review article. For any re- mark please contact the secretary of the BNCPAP 2An update of the 2010 version by Gonze and Weynants, ([email protected]). and the 2005 version by HP Garnir

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1 Numerical and symbolic Some members of the Nanoscopic Physics (NAPS) pole of the Institute of Condensed Matter and models and algorithms for Nanosciences (IMCN) of UCLouvain [7] de- the simulation of physical velop algorithms for the numerical resolution of Schrodinger equation in time, to study the interac- systems tion processes of atoms and molecules with ultra- short electromagnetic pulses. 1.1 Atomic and molecular physics and astrophysics Molecular modeling is also done at Laboratory for Physics of Surfaces and Interfaces (LPSI) of UMons The Institut de Physique Nucléaire, Atomique et [8]. Using the complementary techniques of molec- de Spectroscopie at ULiège [2] has several research ular dynamics (MD), Monte-Carlo simulations, and topics in Computational Physics. The cold atom genetic algorithms, dedicated codes and software physics group develops numerical simulations in are developed providing access to all types of in- the field of cavity quantum electrodynamics with teraction potentials and very large systems of > cold atoms. The atom-field interaction is modeled 1.000.000 particles. Specific modules allow to study in the particular case when the atomic motion must viscosity, surface tension, and static and dynamic be described quantum mechanically and special contact angles. algorithms are used and developed to solve the Schrödinger equation. Cold atoms are very often used in the current thematic of quantum comput- 1.2 Condensed Matter and ers. The group "Theoretical calculations in atomic Nanosystems physics" determines new atomic data related to the radiative and collisional properties of atoms and The ab-initio calculation of the entire structure of ions, based on sophisticated computer codes such a molecule or of an aggregate of atoms (nanostruc- as HFR, SST and MCDF. ture) requires a huge amount of calculations. The ABINIT project [9] initiated in Belgium in 1997 and In the field of atomic physics, and more particularly coordinated in Louvain-la-Neuve is aimed at the atomic spectroscopy, substantial progress has been calculation of such structures and involves a lot achieved by the UMons Astrophysics group (PAAS) a computer code development. On the technical [3] by improving sophisticated computer codes that side the huge code (800000+ lines), freely available, allow to model, in a more and more realistic way, relies on modem techniques for its development, the atomic structures characterized by very complex and the program itself is continuously improved by electronic configurations. more than 50 developers all around the word and has more than 1900 registered users. At UCLou- Along the same line, the ULB "Quantum Chemistry vain, the research mainly focuses inter alea on de- and Atomic Physics" unit of the service of "Chimie velopments in Many-Body Perturbation Theory for quantique et photophysique" [4] focuses on the cal- electronic, transport and optical properties calcula- culation of the structure and dynamics of atomic tions, temperature-dependent and zero-point mo- and molecular species that are relevant in various tion effects on electronic and optical properties, im- fields such as spectroscopy, atmospheric chemistry, proved determination of relaxed atomic geometry astrophysics and astrochemistry, cold molecules, and structural parameters, dielectric properties and nanoelectronics or quantum computing. magnetic responses, and improved functionals for vibrational properties. A new axis of research, high- The Center for Molecular Modeling of UGent throughput calculations, has opened recently. Sim- [5] develops and disseminates [6] several com- ulations based on ab-initio calculations at UCLou- putational tools to facilitate and automate the vain, in the Nanoscopic Physics (NAPS) pole of the analysis of molecules and their dynamics (MD- Institute of Condensed Matter and Nanosciences Tracks, MolMod), to construct molecular models (IMCN) also rely on other software applications (Zeobuilder) or to analyze the electronic structure and cover optical functional materials, carbon-based of molecules (HiPart). nanostructures, materials for nanoelectronics [10].

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At the Physics Department of ULiège, the groups Functional Theory formalism and beyond (GW, of Theoretical Physics of Materials [11], Nanoma- Bethe-Salpeter), to study the structural, electronic, terials [12] and Physics of Solids, Interfaces and optical and magnetic properties of functional ma- Nanostructures [13] are active in extending ab ini- terials. A large part of its work is devoted to the tio tools such as ABINIT, Quantum Expresso, Crys- determination of electron energy core and low loss tal, Octopus and BoltzTrap, in different domains spectra for carbon based materials and metallic : TDDFT, hybrid functionals, molecular dynamics, nanoparticles, whereas optical spectra have been non-linear optical susceptibilities, Raman tensors calculated for TCOs and solar cell absorbers. A and electro-optic coefficients, electrical resistivity, high-throughput methodology is used in combina- electron-phonon coupling, thermoelectric proper- tion with DFT calculations to screen large classes of ties. Most of the main ab initio software packages potential candidate materials with specific proper- are also used for the study of a wide diversity of ties and improved performance. Another important systems: ferroelectric and multiferroic nanostruc- part of the work is devoted to the effect of impuri- tures, 2DEG at oxide interfaces, metals and inter- ties and native defects on the electronic and optical metallics, phase-change materials, liquid semicon- properties of these materials. ductors, nanodiamonds, semiconducting and metal- lic nanostructures, carbon nanotubes, ... The Centre for Molecular Modelling of UGent [5] performs computational material research on the Another group at the ULiège, the group of The- nanoscale. In its quest to design optimal catalysts, oretical Physical Chemistry [14] is modeling the the group aims at predicting, from first principles, electronic, optical and transport properties of dif- accurate rate constants for the chemical kinetics ferent kinds of nanostructures and molecular sys- of catalytic reactions taking place in nanoporous tems. These models are applied to molecular logic materials. Under particular scrutiny are zeolite and could lead to the design of nanosensors. The materials and Metal-Organic Frameworks (MOFs). group is also active in the field of attochemistry and ultrafast molecular dynamics. It develops time- The Laboratory for Physics of Surfaces and Inter- dependent quantum methodologies to follow the faces of UMons [8] studies the properties of material dynamics of coherent electronic wave packets pre- surfaces and their interactions with surrounding pared by ultrashort attopulse in molecular systems, media. Computer modeling is a tool to enhance as well as their probing by photoionization. the performance of a material as regards coating, wetting, adsorption, friction and wear, optics, etc. The Condensed Matter Theory (CMT) group of the Department of Physics of the UAntwerpen The Centre de recherches en Physique de la Matière [15] conducts theoretical research in the area of et du Rayonnement (PMR) of UNamur [17] has a mesoscopic physics and nanophysics. Many com- long experience in numerical modeling for solid puter programs have been developed over the state physics and nanomaterials. Some of their elec- years. Hands-on experience is available on calcu- tronic and optical properties have been explained lations of the strain distribution in self-assembled successfully by researchers of PMR, including e.g. dots, Hartree-Fock approaches, density functional structural coloration of insects. Currently, there is theory, finite difference techniques e.g. to solve a strong focus on carbon nanostructures and two- coupled nonlinear differential equations (e.g. the dimensional materials. The group also has expertise Ginzburg-Landau equations), Monte Carlo simula- in the modeling of nucleation and growth of thin tions, molecular dynamics simulations, variational films and of electron energy loss spectroscopy. quantum Monte Carlo simulations, stochastic vari- ational techniques. For its calculations the group relies on its own clusters of workstations and on 1.3 Particle Physics the UA cluster (see section 3). To predict or analyze the events and experimen- Computational modeling of materials is also a pri- tal signals expected from high-energy accelerators, mary research program of the EMAT group of computational particle physics (CPP) has developed UAntwerpen [16]. First-principles electronic struc- several important tools such as numerical compu- ture calculations are carried within the Density tations on lattice field theory, the automatic calcu-

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lation of particle interaction or decay, event gen- ities and the natural environment. They rely on erators and data reduction software. Several Bel- very complex calculations that are performed by gian groups are active in this area. Variational lat- applying different models that are continuously tice theory and non-perturbative quantum chromo improved. All these calculations involve huge com- dynamics are developed by the Mathematical and puter power and the development of new algo- Theoretical Physics group of UGent [18]. The col- rithms. lider physics simulation tools, developed by the Cosmology, Particle Physics and Phenomenology 1.5 Dynamic systems group at UCLouvain [19] provide all aspects of an event chain and are widely used by the high-energy Included here are physics community at large. Optimization of the 1. Continuous dynamical systems: Hamiltonian Cherenkov detectors of the IceCube Neutrino Ob- systems, Liouvilles’s theorem, dissipative sys- servatory is performed by the Elementary Particle tems, local stability analysis, non-linear oscil- Physics group at UGent [20] by means of detailed lators, bifurcation analysis in one and two di- Monte-Carlo simulations. At the Interuniversity In- mensions. stitute for High Energies IIHE (ULB- VUB) [21] sim- ilar techniques were developed to optimize Positron 2. Discrete dynamical systems: Iterated maps, Emission Tomography detectors. logistic map, cycles and stability, period dou- bling, bifurcations, Lyapunov exponents. The already mentioned high-energy groups of UGent, UCLouvain, ULB and VUB, as well as the 3. Stochastic processes, Brownian motion, Particle Physics team at UAntwerpen [22] exten- stochastic calculus. sively apply the CPP tools in their elaborate partic- A large, coordinated effort is devoted to Dynami- ipation to the data analysis of the Compact Muon cal Systems, their Control and Optimization in the Solenoid and NA62 at CERN and the IceCube po- context of several Interuniversity Attraction Poles lar detectors. In addition, they deploy together an (lAP), which have been running since 1987 and have important High-Energy Physics "Tier-2" computing been extended till 2017 [25]. The work packages center for the CMS experiment that is part of the concern: (i) large scale data and systems, (ii) esti- Worldwide LHC Computing Grid (W-LGG) (see mation and modeling and (iii) distributed systems, section 3). The resources deployed allow the treat- decision, control and communication. This effort is ment of data volumes of unprecedented size and multidisciplinary and finds many applications not complexity in the field of particle physics. just in physics, but throughout the sciences. The Web pages of the partners are: INMA (UCL) [26]; 1.4 Physics of the Globe OPTEC (KUL) [27]; NAXYS (UNamur) [28]; SYS- TEMS (UGent) [29]; ELEC (VUB) [30]; Pôle BIOSYS The GeoHydrodynamics and Environment Re- (UMons) [31]; Systems and Modeling (ULiège) [32]. search group at ULiège [23] uses 3D models of The Federal lAP program is however finished now, marine systems to predict circulation patterns, pol- and a new structure for interregional research has lution dispersion, ecosystem evolution, thermoha- been set up (the EOS funding). line structures of the ocean and many other marine parameters. To do so, a set of coupled non-linear The Department of Applied Mathematics and Com- 3D partial differential equations is solved numer- puter Sciences at UGent [33] works on the develop- ically using finite volume methods. To be able to ment of numerical methods and software for prob- handle the size of the problem (107 state variables lems that can be formulated in terms of differential advanced in time over 104 time steps), parallel com- equations, many of which are inspired by physical puting based on domain decomposition is imple- applications. Particular attention is paid to numer- mented. ical methods and software for dynamical systems of ODEs allowing bifurcations and for the Sturm- The G. Lemaître Centre for Earth and Climate re- Liouville and Schrödinger equations. Among the search of UCLouvain [24] studies the climate evo- developed software MATCONT and MA TSLISE lution and the interaction between human activ- should be highlighted.

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1.6 Astrophysics and Cosmology At the von Karman Institute for fluid dynamics [38], Computational Fluid Dynamics is used to In its development of the Energetic Particle Tele- do research on multiple fields, among them: Tur- scope (EPT), the Center for Space Radiation (CSR) bulence and aero-acoustic effects (Reynolds Aver- [34] of UCLouvain, in collaboration with the Bel- aged Navier-Stokes, Large Eddy Simulation and/or gian Institute for Space Aeronomy [35] is simulating Direct Numerical Simulation); Multiphase flows (by Monte-Carlo methods) the interactions of ener- (Large Eddy Simulation with Volume of Fluids); getic particles present in space with matter or gas Prediction of hypersonic re-entry involving com- by using the CERN developed GEANT software plex multi-physics (Direct Simulation Monte Carlo toolkit [36]. coupled with Finite Volume or Residual Distribu- The Centre for Mathematical Plasma - Astrophysics tion Schemes); Multidisciplinary Optimization & of KULeuven [37] studies space Weather (the pop- Design method with Artificial Intelligence and Neu- ular name for energy-releasing phenomena in the ral Network. magnetosphere) and coordinates the EU-FP7 Space Weather Integrated Forecasting Framework. It de- The Computational Fluid Dynamics group of velops, on massively parallel computers (shared VUB [41] focuses on algorithmic developments for with the Von Karman Institute for fluid dynamics schemes and solvers as well as large eddy simula- [38] specific computational models, based on the tion and its application in different fields such as three-dimensional magneto hydrodynamics (MHD) computational aero acoustics, combustion, biolog- equations as well as kinetic (Particle-in-Cell) sim- ical flows, sedimentation problems, etc. Research ulations. It also creates the software needed to on fluid dynamics is also performed in the Fluid implement such computational models on modem mechanics group of UGent [42] and the group of supercomputers. thermal and fluid engineering at KULeuven [43].

1.7 Physics of Deformable Solids 2 Computational control and and Fluids data processing of Computational physics of deformable solids and fluids is a very important subject for engineering. experiments Because of this reason, research groups will tradi- This topic is one of the concerns of the lAP VII- tionally appear in polytechnic faculties or engineer- DYSCO collaboration mentioned under 1.5[25]. ing schools. For sake of completeness, we neverthe- less mention several groups working in this domain The Laboratory of Biophysics and BioMedical in Belgium. Physics (BIMEF) of UAntwerpen [44] specializes in At UCLouvain, the Institute of Mechanics, Materi- interdisciplinary physics research in the biological als and Civil Engineering [39] develops multi-scale and medial field. The group has three main research modeling for such diverse applications as ocean directions: biomechanics and optical metrology, modeling, crystal growth, the deformation and frac- molecular biophysics and spectroscopy, vestibular ture of advanced metallic alloys, composites and research and medical statistics. Current research bonded joints as well as for cardiovascular and res- topics in computational control and data processing piratory applications. of experiments include the development of electro- optic metrology systems for shape, deformation and The Service "Sciences des Polymères” at ULB [40] vibration measurements in biomedical applications uses statistical mechanics and numerical simulation and biomechanics. and finite element modeling in techniques in order to model at the microscopic biomechanics, with special focus on human middle level the structure as well as processes which take ear and cochlear mechanics, and functional biome- place inside complex states of matter (polymers but chanics in animals. also soft matter). They design and develop simula- tion programs for molecular dynamics techniques, At ULiège, the IPNAS laboratory [3] has con- Monte Carlo or Brownian dynamics. structed many new apparatus that use imbedded

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microprocessors and rely on the virtual instrumen- at VSC. The new Tier-1 supercomputer is equipped tation paradigm [45]. with the latest Intel processors. Also the memory, the internal network and the storage capacity have The Databases and Theoretical Computer Science been adapted, allowing the supercomputer to effi- group of UHasselt [46] new techniques to identify ciently perform complex computations. At time of incompleteness, inconsistencies, inaccuracies and its installation, this new supercomputer was one of errors in databases. the 200 fastest computers in the world. [48]

The main local Tier-2 clusters: 3 Programming and The Tier-2 of UA comprises two clusters. The computational first one, Hopper, consists of 168 nodes (with two 10- core Intel E5-2680v2 Ivy Bridge) developing 75 environments TFlops. Storage capacity is 100 TB. The second cluster, Leibniz, was installed in the 3.1 Belgian research computer spring of 20 17. It is a NEC system consisting of infrastructure 152 nodes with two 14-core intel E5-2680v4 Broad- well generation CPUs connected through a EDR The Belgian computer infrastructure has seen a pro- InfiniBand network. 144 of these nodes have 128 found restructuring over the last decade through GB RAM, the other 8 have 256 GB RAM. The nodes the formation of consortia in the Flemish and the do not have a sizable local disk. [49] French communities. The Tier-2 of VUB (Hydra) consists of 3 clusters of successive generations of processors with a peak The five Flemish University associations have cre- capacity of 75 TFlops (estimated). The total storage ated in 2007 a partnership called Vlaams Super- capacity is 446 TB. It has a relatively large mem- computer Centum [47] aiming to align and inte- ory per computing node and is therefore best fit grate their existing supercomputer infrastructure, for computing jobs that require a lot of memory to make their expertise available to the public and per node or per core. This configuration is comple- private funded research and to construct of a com- mented by a High Throughput Computing (HTC) petitive grid and HPC infrastructure available to grid infrastructure. [50] all researchers in Flanders. The VSC is financed by The Tier-2 of Ghent University (Stevin) represents the Flemish Government. The VSC-infrastructure a capacity of 226 TFlops (11.328 cores over 568 consists of two layers. The central Tier-1 infrastruc- nodes) and a storage capacity of 1,430 TB. It is com- ture is designed to run large parallel jobs. It also posed of several clusters, 1 of which is intended for contains a small accelerator testbed to experiment single-node computing jobs and 4 for multi-node with upcoming technologies. The Tier-2 layer runs jobs. One cluster has been optimized for memory- the smaller jobs, is spread over a number of sites, intensive computing jobs and BigData problems. is closer to users and more strongly embedded in [51] the campus networks. The Tier-2 clusters are also The joint KU Leuven/UHasselt Tier-2 housed by interconnected and integrated with each other. KU Leuven focuses on small capability computing and tasks requiring a fairly high disk bandwidth. The Tier-1 supercomputer: The infrastructure consists of a thin node cluster At the end of October 2016, VSC inaugurated its sec- with 7.616 cores and a total capacity of 230 TFlops. ond Tier-1 supercomputer at the data center of KU A shared memory system with 14 TB of RAM and Leuven, representing an investment of 5,5 million 640 cores yields an additional 12 TFlops. A total euros. The company NEC was selected to build the storage of 280 TB provides the necessary I/O capac- machine through a public tender procedure. This ity. Furthermore, there are a number of nodes with supercomputer, which consists of 580 computing accelerators (including the GPU/Xeon Phi cluster nodes with two 14-core Intel Xeon processors, has purchased as an experimental tier-1 setup) and 2 a processing power of more than 600 TFlops, the visualization nodes. [52] equivalent of 2000 fast PCs. It has a capacity that is three times that of the first Tier-1 supercomputer The VSC system is mostly used for space weather

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calculations, fluid and plasma dynamics, nanotech- nodes are interconnected by a Gigabit Ethernet net- nology, modeling of materials, biophysics, bioinfor- work and have access to three NFS file systems for matics and computational chemistry. a total capacity of 98 TB. [56] The Tier-2 of ULB (vega) features 44 fat compute In 2010, the 5 universities of the French-speaking nodes with 64 cores (four 16-cores AMD Bulldozer community of Belgium created the "Consortium des 6272 processors at 2.1 GHz) and 256 GB of RAM, in- Équipements de Calcul Intensif" (CECI) [53], that is terconnected with a QDR Infiniband network, and supported by the F.R.S.-FNRS. The main facilities of 70 TB of high performance GPFS storage. [57] the consortium also comprise a Tier-1 and a Tier-2 The Tier-2 of ULiège (nic4) consists of 128 compute infrastructure. nodes with two 8-cores Intel E5-2650 processors at 2.0 GHz and 64 GB of RAM (4 GB/core), intercon- The Tier-1 supercomputer: nected with a QDR Infiniband network, and having The Tier-1 supercomputer (zenobe) consists of two exclusive access to a fast 144 TB FHGFS parallel parts with nearly 14,000 computing cores result- filesystem. [58] ing from an investment of nearly 5.5 million euros, The Tier-2 of UCLouvain comprises two clusters. achieved in three stages: Lemaitre2 comprises 112 compute nodes with two • a calculator acquired in 2011 constituting a 6-cores Intel E5649 processors at 2.53 GHz and 48 base of approximately 3300 calculation cores, GB of RAM (4 GB/core). The cluster has exclusive access to a fast 120 TB Lustre parallel filesystem. • its extension financed by the grant PRACE All compute nodes and management (NFS, Lustre, Supercomputer Tier-1 of the Walloon Region, Frontend, etc.) are interconnected with a fast QDR adding at the end of 20 13 about 8200 comput- Infiniband network. This cluster will be replaced in ing cores to this base, and 2018. [59] Hmem mainly features 17 fatnodes with 48 cores • the renewal, at the end of 2015, of the calcula- (four 12-cores AMD Opteron 6174 processors at 2.2 tion nodes acquired 4 years earlier, providing GHz). 2 nodes have 512 GB of RAM, 7 nodes have 5760 computing cores of the latest architecture. 256 GB and 7 nodes have 128 GB. All the nodes are The Tier-1 configuration was put into operation in interconnected with a fast Infiniband QDR network July 2014. It has a sustained computing capacity of and have a 1.7 TB fast RAID setup for scratch disk more than 330 TFlops. Its best position in the world space. All the local disks are furthermore gathered ranking of the 500 most powerful calculators was in a global 31 TB Fraunhofer file system (FHGFS). recorded in November 2014 in 300th place. [54] [60]

The main local Tier-2 clusters: The Belgian WLCG CMS "Tier-2" computing project The Tier-2 of UMons (dragon1) is a cluster of 26 for data analysis of the CMS experiment at the computing nodes, each with two Intel Sandy Bridge CERN laboratory, which was mentioned in section 8-cores E5-2670 processors at 2.6 GHz, 128 GB of 1.3, consists of two physical clusters, one being lo- RAM and 1.1 TB of local scratch disk space. The cated in Brussels [61] and one in Louvain-la-Neuve compute nodes are interconnected with a Gigabit [62]. These two clusters also integrate computing Ethernet network (10 Gigabit for the 36 TB NFS file resources for the IceCube and NA62 experiments as server). Two additional nodes have two high-end well as the high energy physics simulation project NVIDIA Tesla 2175 GPUs (448 CUDA Cores/6GB MadGraph. As of January 2018, the two centers GDDR5/515Gflops double precision). [55] offer 7000 cores of processing power and 5000 TB The Tier-2 of UNamur (hercules) consists of ap- of disk storage. proximately 900 cores spread across 65 compute nodes. It mainly comprises 32 Intel Sandy Bridge Belgian scientists can also respond to calls for nodes, each with two 8-core E5-2660 processors at proposals from PRACE [63], the EU partnership for 2.2 GHz and 64 or 128 GB of RAM (8 nodes), and Advanced Computing in Europe, that manages the 32 Intel Westmere compute nodes, each with two following Tier-0 resources: X5650 6-core processors at 2.66 GHz and 36 GB ,72 - The 2 PFlops CURIE facility ofCEA, Bruyeres-Le- GB (5 nodes) or 24 GB (5 nodes) of RAM. All the Chatel, France [64]

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- The 5.9 PFlops WQUEEN facility at Forschungzen- exploration, integration options and advanced char- trum Juelich (FZJ), Julich, Germany [65] acterization towards process technology platforms - The 6.8 PFlops SuperMUC of the Leibniz Super- applicable in high-volume manufacturing of future computing Centre (LRZ) Garching, Germany [66] logic and memory ICs. All research carried out is - The 7.4 PFlops HAZEL ZEN facility at Hoechstleis- inextricably linked with quantitative material and tungsrechenzentrum (HLRS) Stuttgart, Germany device characterization and reliability analysis. [67] - The 11.1 PFlops MARENO STRUM facility at the Barcelona Supercomputing Center (BSC), Barcelona, 5 Conclusions Spain [68] - the 13 PFlops MARCONI facility of CINECA, Even if this review is not exhaustive, it proves that Bologna, Italy [69] computational physics activity in Belgium is im- - the 19.6 PFlops PIZ DAINT facility of Swiss portant and that a lot of physics groups are active National Supercomputing Centre (CSC), Lugano, in the field. Computer programs are developed Swiss [70] and improved in almost all universities often as byproducts of main researches.

3.2 BELNET and BEgrid In Belgium, the universities, colleges, schools, re- References search centers and government departments are connected by a national research network that pro- [1] www.iupap.org/commissions/computational- vides high-bandwidth Internet connection. This physics/mandate infrastructure, called BELNET [71], has been initi- ated in 1989 by the Belgian Science Policy Office’s [2] www.ipnas.ulg.ac.be/ programming department, with the aim of enabling [3] http://hosting.umons.ac.be/html/agif/Teams.html intensive transfer of data between scientists, and remote connections to powerful computers. [4] http://www.ulb.ac.be/cpm/theory.html In 2003, BELNET started a new project called BE- grid [72], the computing/data grid infrastructure of [5] https://molmod.ugent.be the Belgium Grid for Research. The general princi- [6] https://molmod.ugent.be/software ple of grid computing consists in the availability of a network that connects geographically spread com- [7] http://uclouvain.be/en/research- puting and storage resources while giving many institutes/imcn/naps user groups access to the network. Grid computing means in fact globalization and virtualization of [8] https://sharepoint1.umons.ac.be/fr/universite computer infrastructures. Current participants to /facultes/fs/services/institut_physique/ BEgrid, and providers or resources are KULeuven, physique_surfaces_interfaces/pages/default.aspx UAntwerpen, UGent, ULB, Vlaams Instituut voor [9] www.abinit.org de Zee (VLIZ), VUB, and CETIC. [10] http://uclouvain.be/en/research- institutes/imcn/naps/numerical-simulation- 4 The physical basis of at-the-nanoscale.html computer machinery [11] http://www.materials.ulg.ac.be/cms/c_7705/ theoretical-physics-of-materials The Interuniversity Microelectronics Centre (lMEC [73]), is heavily involved in the research aiming at [12] www.nanomat.ulg.ac.be the reduction of the size and power dissipation of [13] www.spin.ulg.ac.be computer chips. Its efforts encompass material and transistor architecture studies, tool and process step [14] www.tcp.ulg.ac.be

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[15] www.uantwerpen.be/en/rg/cmt [42] www.ugent.be/ea/floheacom/en/research/ groups/flow [16] www.uantwerpen.be/en/rg/emat [43] www.mech.kuleuven.be/en/tme/research/thermal [17] http://pmr.unamur.be [44] www.uantwerpen.be/en/rg/bimef [18] http://mathphy.ugent.be/wp/mtp [45] www.ipnas.ulg.ac.be/laboipnas/recherches/ [19] http://cp3.irmp.ucl.ac.be/ColliderPhysics recherches.html Simulation [46] http://alpha.uhasselt.be/research/groups/theocomp [20] http://inwfsun1.ugent.be/onderzoek.php #IceCube [47] www.vscentrum.be

[21] http://w3.iihe.ac.be/experiments.php?exp=7 [48] www.vscentrum.be/en/access-and- infrastructure/tier-1 [22] www.uantwerpen.be/en/rg/particle-physics- group [49] www.vscentrum.be/infrastructure/hardware/ hardware-ua [23] http://modb.oce.ulg.ac.be [50] www.vscentrum.be/infrastructure/hardware/ [24] http://uclouvain.be/en/research- hardware-ugent institutes/eli/teclim [51] www.vscentrum.be/infrastructure/hardware/ [25] http://sites.uclouvain.be/dysco hardware-vub

[26] http://uclouvain.be/fr/node/2107 [52] www.vscentrum.be/infrastructure/hardware/ [27] http://set.kuleuven.be/optec hardware-kul

[28] www.naxys.be [53] www.ceci-hpc.be

[29] www.systems.ugent.be [54] http://tier1.cenaero.be/fr/zenobe

[30] http://vubirelec.be [55] http://www.ceci- hpc.be/clusters.html#dragon1 [31] http://tcts.fpms.ac.be/biosys/index.html [56] http://www.ceci- [32] www.montefiore.ulg.ac.be/services/stochastic hpc.be/clusters.html#hercules /new/doku.php?id= [57] http://www.ceci-hpc.be/clusters.html#vega [33] http://www.ugent.be/we/twist/en [58] http://www.ceci-hpc.be/clusters.html#nic4 [34] http://web.csr.ucl.ac.be/uclelicsr [59] http://www.ceci- [35] www.aeronomie.be/ hpc.be/clusters.html#lemaitre2

[36] http://geant4.cern.ch [60] http://www.ceci- hpc.be/clusters.html#hmem [37] http://wis.kuleuven.be/CmPA [61] http://w3.iihe.ac.be [38] www.vki.ac.be [62] http://cp3.irmp.ucl.ac.be/HPC [39] http://uclouvain.be/fr/node/3404 [63] www.prace-ri.eu [40] www.ulb.ac.be/sciences/polphy/Sciences _des_Polymeres [64] http://www-hpc.cea.fr/en/complexe/tgcc- curie.htm [41] http://mech.vub.ac.be/thermodynamics/ re- search_topics.htm [65] www.fz-juelich.de/ias/jsc/juqueen

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[66] www.lrz.de/services/compute/supermuc

[67] www.hlrs.de/systems/cray-xc40-hazel-hen

[68] www.bsc.es/marenostrum/marenostrum

[69] www.cineca.it/en/content/Marconi

[70] www.cscs.ch/computers/piz-daint

[71] www.belnet.be

[72] www.begrid.be

[73] www.imec-int.com/en/home

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Research Activities in Hard Condensed Matter and Semiconductor Physics in Belgium

Ewald Janssens - Yvan Bruynseraede

Laboratory of Solid-State Physics and Magnetism Department of Physics and Astronomy - KU Leuven Celestijnenlaan 200 D, BE-3001 Leuven

1 Condensed Matter and Semiconductor Physics is into magnetic, semiconducting, dielectric and su- remarkable for the breadth and depth of its impact perconducting systems. Specifically, the overall on physics as well as on other scientific disciplines. goal is to understand the above physical proper- It is a very active field, with a stream of discoveries ties in systems with reduced dimensionality and in areas ranging from superconductors and semi- nanoscale confinement of charge, spin and pho- conductors to the optical, electronic, magnetic, and ton. The systems studied range in size from three- mechanical properties of materials and devices. It dimensional thin film heterostructures to individ- includes the study of well-characterized solid sur- ual nanoscale clusters. The laboratory has out- faces, interfaces and nanostructures. standing thin film and atomic cluster preparation The following briefly describe the main research expertise, with a range of in-situ characterization activities at Physics Departments of Belgian Uni- and nano lithographic patterning techniques. Sam- versities. The text is not an exhaustive review but ple characterization and measurement is under- mentions the topics studied in various laboratories. taken using state-of-the-art equipment including For more details we refer to the website addresses. a range of advanced scanning-probe microscopes, low-temperature systems for transport and magne- tization measurements, Raman and photolumines- 1 University of Leuven cence spectroscopes.

1.1 The Laboratory of Solid-State 1.1.1 The Research Group ”Nanoscale Physics and Magnetism (VSM) Superconductivity & Magnetism”

Website: http://fys.kuleuven.be/vsm/ Website: https://fys.kuleuven.be/vsm/nsm

The laboratory is a leading center for research The main objective is to investigate the effect of nanoscale confinement on the electrical, magnetic, 1The Belgian National Committee for Pure and Ap- plied Physics (BNCPAP) is responsible for the con- and optical properties of materials. The group tent of the present review article. For any re- wants to reveal the fundamental relation between mark please contact the secretary of the BNCPAP quantized confined states and physical properties ([email protected]). of these materials: principle of "quantum design".

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Scientifically, quantum design is a challenging ob- 1.1.4 The Research Group ”Functional jective in condensed matter physics, since it bridges Nanosystems” the gap between physics of single atoms and bulk Website: https://fys.kuleuven.be/vsm/fun/index solids. A variety of state-of-the-art preparation and research equipment are used. The current re- The group focuses its research on advanced nano- search topics include superconducting nanostruc- materials and their assembly into functional de- tures, vortices in superconductors, superconduct- vices and systems. Advanced nanomaterials in- ing/ferromagnetic hybrids, and plasmonic nanoan- clude nanoparticles, 2D nanostructures, thin film tennas. heterostructures, and bio-hybrids. They explore their functional response, important for many ap- 1.1.2 The Research Group ”Clusters and plications in fields like electronics, materials science, Laser Spectroscopy” catalysis, energy production and medicine. The ap- proach covers experimental and theoretical efforts Website: https://fys.kuleuven.be/vsm/class as well as nanoscale up to macroscale synthesis and characterization. Research topics include nanomate- The group focuses on condensed matter down to rials (carbon nanotubes and carpets, nanowires and the atomic scale where finite size effects, including nanoparticles), oxide-semiconductor interfaces, ma- in particular quantum confinement and electron terials with metal-insulator transitions, and novel correlations, become dominant. The challenge is functional materials for rechargeable batteries. to understand and develop the tunability of phys- ical properties as matter is assembled from indi- 1.2 The Institute for Nuclear and vidual atoms towards bulk systems. The aim is to understand and tailor the unique properties of Radiation Physics (IKS) clusters of a few up to several 100 atoms and in- Website: http://fys.kuleuven.be/iks/ duce new properties in cluster-assembled and low- dimensional systems. Research ranges from studies 1.2.1 The Research Group ”Nuclear Solid of the physics and chemistry of small clusters in the gas phase using laser spectroscopy and mass spec- State Physics” trometry over investigations of individual clusters Website: http://fys.kuleuven.be/iks/nvsf/home on surfaces with scanning probe techniques. The research is concentrated on four different do- mains: magnetic nanostructures, silicides and ger- 1.1.3 The Research Group ”Scanning manide thin films, doping of semiconductors, sur- Probe Microscopy” faces and nanoparticles. The group has access to a Website: https://fys.kuleuven.be/vsm/spm variety of experimental conventional and nuclear techniques. The current research topics include:

The study of physical processes occurring at the • magnetic nanostructures studied for their in- nanometer scale has been substantially upgraded teresting fundamental properties and appli- by the development of scanning probe microscopy cations; (SPM). A whole family of scanning probe varieties has been and is being developed, providing un- • doping semiconductors for applications in e.g. precedented access with nanometer resolution to magnetic storage media; the structural properties as well as to the nanometer • silicide and germanide thin films as essential parts scale variations of various other physical properties, of microelectronic devices; and including the local electrical, magnetic and mechan- ical behaviour. The group has access to state-of-the- • surfaces and nanoparticles such the structure of art SPM facilities and research topics include quan- (passivated) semiconductor surfaces (Si, Ge, tum confinement in metallic nanoparticles, finite- GaAs, InGaAs, ... ) and the growth of nanos- size effects in patterned ferromagnets, and proper- tructures on these surfaces as well as embed- ties of carbon nanotubes and biomolecules. ded nanoparticles created by ion implantation.

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1.3 The Laboratory for 2.1 The Research Group ”Electron Semiconductor Physics Microscopy for Materials

Website: http://fys.kuleuven.be/hf/ Research ”(EMAT) Website: www.uantwerpen.be/en/rg/emat/ The laboratory is experimentally oriented and prin- cipally addressing semiconductor/insulator het- EMAT is one of the leading electron microscopy erostructures and amorphous materials of reduced centers in the world and has expertise in both fun- dimensions. The main focus is on interfacial elec- damental and applied electron microscopy. Its goal trical and structural properties. The approach is is the study of (inorganic) materials by different a combination of interface-specific experimental electron microscopy techniques. It has built up a methods sensitive to local atomic structure, and wide range of activities concerned with fundamen- methods to probe both the extended and localized tal solid state physics, materials science, solid state spectrum of electron states. The experimental tech- chemistry, and materials characterization. With niques used are: Electron Paramagnetic Resonance decreasing dimensions down to the nanometer (EPR) which is virtually the sole method of iden- and sub-nanometer scale, electron microscopy is tification of point defects at the atomic scale; In- a unique technique, being able to relate structural ternal Photoemission Spectroscopy (IPS) for the properties to physical or chemical properties. In- determination of band diagrams of semiconduc- creased understanding of the basic phenomena in- tor/insulator structures; and Inelastic Electron Tun- volved in the interaction of electron beams with nelling Spectroscopy (lETS) for interface characteri- materials and improved computer power allow to zation at a length scale below 2 nm. better determine the local structure, the local com- position and even the local electronic structure. This 1.4 The Institute for Theoretical is applied to a wide field of materials such as semi- Physics conductors, superconductors, alloys, polymers cat- alysts and small particles, surface layers, multilay- Website: http://itf.fys.kuleuven.be/ ers and composite materials. Advanced electron microscopy not only involves resolution at the sub- 1.4.1 The Research Group” Interfaces and nanometer level, it also includes advanced diffrac- Wetting” tion techniques for determining the local structure and analysis of the inelastic scattered electrons to Website: http://itf.fys.kuleuven.be/∼joi/ obtain compositional and electronic information. EMAT has several state-of-the-art electron micro- The main areas of research interest are wetting scopes including two aberration corrected, high end transitions, novel fractal structures, topological- FEI- Titan instruments, a dual beam FIB, and an dependent interactions and biased percolation on environmental SEM. The following list gives the scale-free networks. The wetting phase transition major current research themes investigated: shape is illustrated through its occurrence in a variety of memory alloys, multiferroic materials, ceramic thin condensed matter systems, ranging from classical films, nanostructured materials, carbon based mate- fluids to superconductors and Bose-Einstein con- rials, zeolites and mesoporous materials, soft matter densates. Currently special attention is devoted to and polymers. i) the study of physical and interdisciplinary appli- cations of novel fractal structures including hierar- chical deposition! population models and bio film 2.2 The Research Group structures, and ii) topology-dependent interactions ”Experimental Condensed and percolation in scale-free networks including Matter Physics” (ECM) degree-dependent interactions. Website: https://www.uantwerpen.be/en/rg/ecml 2 University of Antwerp The group investigates a range of topics such as

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high-spin molecular compounds, point defects in The group studies systems for which quantum me- wide bandgap materials, electro-optical and non- chanical behavior becomes macroscopic, e.g. su- linear optical molecules, materials for organic elec- perconductors, liquid helium, atomic superfluids, tronics including photovoltaic’s, carbon nanotubes and polariton superfluids. Feynman’s path integral and crystalline nanostructures. State-of-the art in- theory is the tool of choice to study their behavior. strumentation is available for continuous wave and They look for quantum behaviour in several specific pulsed electron paramagnetic resonance (EPR) in X- areas: and W-bands, high-sensitivity fluorescence, Raman • scattering, and pulsed laser experiments for time- in solids: investigation of mechanisms for su- resolved optical spectroscopy and nonlinear optics. perconductivity and modeling how supercon- The main research themes are high-frequency EPR ducting properties can be modified by nanopat- of high-spin transition metal compounds, point de- terning. For example studies of collective exci- fects in wide band-gap materials, photographic ma- tations of electrons in plasmonics, interplay of terials, semiconductor nanostructures and devices, light and metallic nanoparticles, and quantum organic electro-optic materials, and organic non- dots. linear optics. • in atomic gases: superfluidity and Bose-Einstein condensation in ultracold atomic gases, both bosonic and fermionic. The adjustability of the 2.3 The Research Group interatomic interaction strength, the possibility ”Condensed Matter to build artificial gauge fields into the effec- Theory”(CMT) tive Hamiltonians, and the versatility of the confinement geometry are used. Website: https://www.uantwerpen.be/en/rg/cmt/ • in condensed light: Photons in a cavity can be hy- bridized with excitons, and form polaritons, re- sulting in a fluid of interacting photons with a The group concentrates on the theoretical study small effective mass. In the appropriate regime of materials (semiconductors and superconductors) of temperatures and density, this also becomes of micrometer and nanometer size. Their electri- a superfluid. cal, magnetic and optical properties are studied us- ing theoretical modeling and computer simulations. New hybrid systems consisting of combinations of 3 University of Ghent semiconductors and ferromagnets or superconduc- tors are investigated. The goal is the increase of 3.1 Department of Solid State the functionality of semiconductor structures. The main research subjects are: i) graphene which is Sciences a unique single layer material with extremely un- Website: https://www.ugent.be/we/solidstatesciences/en/ usual properties; ii) superconductivity with focus on the properties of the vortex matter in various The department has activities in the broad field of structures; iii) colloids by employing molecular dy- Solid State Sciences related to deposition and (sur- namics to study properties of interacting particles; face) analysis of thin films, to magnetron deposi- and ab initio calculations to gain insight into the tion, conformal coating of nanomaterials, detection new or even hypothetical materials. and microscopic characterization of paramagnetic defects in solids by means of Electron Paramag- netic Resonance (EPR) and Electron Nuclear Dou- 2.4 The Research Group ”Theory of ble Resonance (ENDOR). It includes also the study Quantum Systems and of defects in semiconductors, i. e. physical proper- Complex Systems” (TQC) ties, identification, quantification of analytical tech- niques and the growth & characterization of photo- Website: https://www.uantwerpen.be/en/rg/theory-and electroluminescence of sulfide phosphors. At of-quantum-sy/ present the department counts 6 research groups.

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3.1.1 The Research Group ”Conformal 3.1.4 The Research Group ”Dynamics of Coating of Nanomaterials” (CoCoon) Functional Nano Materials (DyNaMat)

Website: http://www.cocoon.ugent.be/ Website: https://www.ugent.be/we/solidstatesciences/ dynamat The research of CoCoon is situated within the con- tinuing trend towards miniaturization in micro- DyNaMat’s research activities cover various sub- electronics. The group focuses on all levels of thin jects in the domain of magnetism: film devices, from deposition to their different ap- plications after extensive characterization. The re- • Skyrmions and chiral systems: ferromagnet films search activities are concentrated on deposition of can be chiral due to the Dzyaloshinskii-Moriya thin films (atomic layer deposition of conformal nteraction (DMI) induced by symmetry break- nanocoatings and combinatorial deposition of thin ing at interfaces. This chiral interaction is stud- film materials libraries), characterization of thin ied in spin structures such as spin spirals, spin films (in situ during deposition - ex situ at syn- cycloids, and skyrmions. chrotrons), and applications of thin films (nano- electronics, solar cells, non-volatile memories, and • Exchange bias: wheen cooling a ferromag- Li-ion batteries). netic/antiferromagnetic bilayer in a magnetic field below the Neel temperature, an unidirec- 3.1.2 The Research Group ”Defects in tional shift of the hysteresis loop is observed. Semiconductors (DISC) This shift is accompanied by an enhanced co- ercivity. The influence of this interface interac- Website: https://www.ugent.be/we/solidstatesciences tion on FMI AFM bilayers is studied. /en/research/groups/disc • Artificial spin ice: in some magnetic systems in- The research of DISC focuses on the study of de- teractions result in the inability to minimize all fects in semiconductor materials in order to explain its competing interactions, called frustration. their effects on electrical and optical properties of An example of a frustrated system is water ice. semiconductor devices. The semiconductors stud- The ordering of the magnetic moments in a ied are Si, Ge, diamond, III - V, II -VI and Cu(ln!Ga square lattice of magnetic islands is studied. )Se2, with applications in microelectronics, optoelec- tronics and photovoltaics. Defects are investigated • Domain wall motion. When the magnetization trough their electronic, vibrational, and electron at two ends of a nano strip are aligned anti par- magnetic resonance spectra. The aim is to obtain allel, there will be a small region in between information on the physical properties, structural where the magnetization turns 180 degrees. identification, and quantification of defects via vari- These regions are called domain walls. The ous electrical characterization and (quasi) spectro- group studies the mobility of a domain wall scopic techniques. under the influence of disorder, thermal fluctu- ations, and driving forces like magnetic fields and spin polarized currents. 3.1.3 The Research Group ”Dedicated Research on Advanced Films and Targets” (DRAFT) 3.1.5 The Research Group ”Electron Magnetic Resonance” (EMR) Website: http://www.draft.ugent.be/ Website: https://www.ugent.be/we/solidstatesciences/ The research group DRAFT studies magnetron sput- en/research/groups/EMR ter deposition in general. Beside the research of industrial interesting materials such as supercon- The EMR group studies the microscopic structure ductors or (photo )catalytic systems, the focus is on of paramagnetic point defects in solids by means of fundamental aspects of reactive sputter deposition. Electron Magnetic Resonance (EMR) Spectroscopy. The long tradition in magnetron sputtering resulted They are known for detailed characterization of in an international status on reactive sputtering. paramagnetic centers, but also for the use of high

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sensitive and non-destructive techniques. The re- as magnetic oxides, nanomaterials, thin films, iron- search is focused on irradiation damage of organic nickel meteorites, minerals, clays, high pressure crystals, transition-metal or lanthanide activated synthesized minerals, Fe-bearing precursors for car- optical materials and semiconductors. The group bon nanotubes. In the field of positron annihilation uses ESR (Electron Spin Resonance) also known as the interest is mainly in defects in metals and alloys, EPR (Electron paramagnetic resonance), ENDOR and the many aspects of the behavior of positron- (Electron Nuclear Double Resonance), and EI-EPR ium in insulating materials. (ENDOR-induced EPR).

3.1.6 The Research Group” Luminescent 4 University of Hasselt: The Materials” (LumiLab)

Website: http://www.lumilab.ugent.be/ Institute for Material Research (IMO) The LumiLab group brings together various do- mains of light research: Website: https://www.uhasselt.beIUH/IMO/About- • LED phosphors, mainly binary and ternary IMO-IMOMEC sulfides for wavelength conversion in white LEDs; The Institute is a research centre with a vast knowl- • persistent luminescence, glow-in-the-dark ma- edge in the field of materials science. It has an inten- terials and their perceived brightness; sive collaboration with IMOMEC, the department of IMEC at the university campus. While most of the • non-aqueous sol-gel synthesis and protection more fundamental research is carried out at IMO, of particles by coating, solvothermal synthesis; the largest part of applied research and projects in collaboration with industry are concentrated • X-ray absorption spectroscopy as a tool to in- within IMOMEC. Within IMO, Physics Materials vestigate rare earth ions in host crystals; and Research is conducted in a number of subgroups. • photocatalysis for fast removal of volatile or- Website: https://www.uhasselt.beIUH/IMO/Visit- ganic molecules and air purification. the-groups/

Various facilities are available such as fluores- cence spectrophotometry, absorption spectroscopy, 4.1 The Research Group ”Energy decay measurements, ellipsometry, X-ray diffrac- tion, and scanning electron microscopy. Materials and Interfaces” (EMINT) 3.2 The Research Division ”Nuclear This group aims to gain mechanistic insight into Materials Physics ”(NUMAT) reactions of materials and interfaces. Research fo- Website: http://www.numat.ugent.be/ cuses on electrochemical interfaces, in particular related to positive electrodes of Li-Ion Batteries, but The division is dedicated to the study of funda- also on electrodeposition and corrosion. Chemi- mental and technological properties of materials cal and electrochemical reactions take place on the by means of experimental methods, which use nu- molecular or atomic scale requiring high-resolution clear radiations or the interactions of the nuclei techniques to gain deeper understanding. Next with electromagnetic fields. They concentrate on to common laboratory-based techniques and other Mossbauer spectroscopy and positron annihilation more advanced structural methods such as Atom spectroscopy. Mossbauer spectroscopy can be per- Probe Tomography, the group further employs in- formed only on a limited number of isotopes of situ X-ray diffraction using synchrotron light. which the most important is 57Fe. Therefore the re- search is mainly on iron-containing materials such

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4.2 The Research Group 4.5 The Research Group ”Engineering Materials & ”Nanostructure Physics” (NSP)

Applications” (EMAP) The NSP group focuses its research on fundamen- tal topics in nanometer-scale science and technol- The group is active in electronics and electro- ogy with emphasis on new materials (mainly metal mechanics. The applied research is situated within particles and organic/inorganic hybrid structures). three domains. In the domain of "Biomedical Device The main goal is the understanding of physical Engineering" the research focuses on the develop- and chemical properties related to the reduced di- ment of dedicated measuring platforms that can mensions of nanostructured materials; including process the signals of sensors and thermal or opti- electronic & atomic (molecular) structure, charge cal based biosensors into a fully functional point-of- transport, optical, magnetic, and thermodynamic care system. In the domain of "Energy Systems En- properties, and chemical reactivity. gineering" the research is concentrated on materials for photovoltaics and batteries. The primary inter- est lies in the reliability of the components. In the 4.6 The Research Group ”Design domain of "Functional Materials Manufacturing" and Synthesis of Organic different printing and coating processes are used Semiconductors” (DSOS) such as inkjet printing, screen printing or spray coating onto different substrates. Research is focused on the design, synthesis and characterization of small organic molecules, oligomers and polymers for application in plas- 4.3 The Research Group tic and advanced healthcare. Besides the study of ”Photonics and Quantum Lab” novel synthetic methods, modifications of existing (PQL) polymerization pathways are developed. Attention is paid to the development of new materials, fun- This group addresses cross disciplinary scientific damentals and concepts in organic semiconductor topics of photonics, optical device physics and biol- technology. A broad pallet of advanced electronic ogy. It uses nanofabrication tools to fabricate semi- materials is available for further studies in devices, conducting and quantum physics based devices, e.g. light-emitting diodes (OLEDs), organic field- which are used to probe and image semiconducting effect transistors (OFETs), organic photovoltaic de- and biological systems at the nanoscale. vices (OPVs), organic photodetectors (OPDs) and chemo- or biosensors.

4.4 The Research Group 4.7 The Research Group ”Wide ”Functional Materials Bandgap Materials” (WBGM) Engineering” (FME) The group is active in the field of wide bandgap The FME group investigates printing and coating materials with emphasis on the deposition and char- techniques of functional materials on different sub- acterization of CVD diamond films. The properties strates. The focus is threefold: i) Investigation to- of novel materials like hexagonal boron nitride (h- wards the printability of functional materials, or- BN) nanowalls and thin piezoelectric aluminium ganic materials, and scratch and wear resistant ma- nitride (AIN) layers are also investigated. Recently, terials. ii) Deposition of these materials on different the emphasis is on the use and functionalization of substrates (glass, foil, paper, textiles) using print- nanodiamond particles and film surfaces with small ing and coating techniques. The properties are molecules. Besides fundamental research, like the determined using characterization techniques for nucleation and doping of diamond, the materials opto-electronic, thermal and mechanical investiga- are used in structures like "solar-blind" UV detec- tions. iii) Application of the functional materials tors, or acoustic wave sensors based on heterostruc- and upscaling towards use in organic electronics tures of nano- and microcrystalline diamond with (solar cells, light emitting devices ... ). piezoelectric materials like AIN.

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4.8 The Research Group ”Organic dynamics of semiconductor lasers, non-equilibrium Opto-Electronics” (OOE) pattern formation, and solitons dynamics. The fol- lowing research lines can be distinguished. The OOE group aims to understand fundamental opto-electronic processes in organic and molecu- • Dynamics of semiconductor lasers. Nonlinear dy- lar semiconductors and exploit them for organic namics, bifurcation theory and stochastic pro- electronic applications, with a main focus on pho- cesses are used in lasers, in particular semi- tovoltaics. Charge carrier generation and recombi- conductor lasers. This theoretical study allows nation in these materials are dictated by the prop- investigating the dynamic behavior of semi- erties of excited electronic states at organic donor- conductor lasers. These theoretical predictions acceptor interfaces, such as excitons and charge are tested experimentally. transfer states. They search for structure-property relations, guiding the synthesis of new materials • Coherent properties of lasers. Research of meth- with improved performance in devices such as solar ods to modify and control the spatial coher- cells, photo-detectors and light emitting diodes. ence in order to generate spatially incoherent emission of a laser source. The objective is to 4.9 The Research Group ”Electrical understand, model, optimize and apply this unique emission regime in innovative applica- and Physical Characterization tions. (ELPHYC) • Metamaterials. Study of complex structures The group is active in the characterization of mate- that are composed of small, resonant electric rials systems and microelectronic components us- circuits. These building blocks are smaller than ing high resolution in-situ measurement techniques. the wavelength of light. The problems stud- Activities involve analytical & electrical character- ied range from the simulation of elementary ization of materials systems and/or experimental metamaterial building blocks, over photonic sensor devices. The focus is on the development of devices, to the development of meta material- electronic interfaces for biosensors and the devel- based systems. opment of reliability equipment for solar cells and modules. The group also acts as a major service • Dissipative solitons. Study of structures that center towards industry with services from laser op- arise in extended spatial systems in nature, tics to biomedical devices and from raw materials both patterns as well as localized structures. to solar panels or high speed processors. Investigation of the dynamic behavior of soli- tons, study of the fundamental principles, and unraveling the underlying bifurcation struc- 5 University of Brussels ture. (VUB): The Research Group • Coupled networks with delay. With such systems, ”Applied Physics”(APHY) synchronization may occur in which the oscil- lators vibrate with the same frequency and/or Website: http://we.vub.ac.be/aphy/ phase. The systems have universal data pro- cessing properties (reservoir computing or liq- The Applied Physics group is a multidisciplinary uid state machines) that are investigated. group of researchers from the Departments of Physics and of Applied Physics & Photonics. They • Nonlinear oscillators with delay. Those delay sys- use experimental and theoretical methods to ad- tems have universal information processing dress fundamental challenges in biological physics, properties. With a single non-linear node one condensed matter physics, electromagnetism, laser can achieve the same computational perfor- physics and photonics. The main research themes mance as with a neural network. The investiga- are the study of metamaterials and nanophotonics, tions are related to the information processing bio-inspired approaches to machine learning, the capacity and the computational properties.

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6 Universite´ Catholique de 6.1.2 Functional Hybrid Multi Segmented Louvain: The ”Institute of Nanotubes and Nanowires Condensed Matter and The membrane-template method is combined with layer-by-layer (LbL) assembly and/or electrodepo- Nanoscience” (IMCN) sition to sequentially synthesize multi segmented nanostructures composed of metals, polymers, syn- Website: https://uclouvain.be/en/research- thetic and biological poly electrolytes, and col- institutes/imcn/research-divisions.html loids. The electrochemical approach controls the architectural parameters of the resulting structures, Research is focused on condensed matter and whereas the LbL adsorption technique permits to nanoscience from the atomic and molecular levels to integrate non conducting materials. real materials. The research concerns the synthesis, design, manipulation, implementation and model- 6.1.3 Hybrid materials for Potential ing of (bio-) molecules, (bio-) surfaces and solid Thermoelectric Applications materials. The compounds, materials or devices are investigated for their functions, properties or Thermoelectric materials are interesting due to their reactivity, leading up to applications. The institute ability to convert energy for cooling (Peltier effect) consists of three research divisions (BSMA, MOST, and electric power generation (Seebeck effect). The NAPS). The divisions and research groups related performance of thermoelectric materials depends to condensed matter physics and semiconductors on the dimensionless figure of merit including the are briefly described hereunder. temperature, athe Seebeck coefficient, the electrical resistivity and the thermal conductivity. 6.1 Research Division ”Bio-and Soft Matter” (BSMA) 6.1.4 Hybrid Systems for EM Absorption and Metamaterial Properties Website: https://uclouvain.be/en/research- institutes/imcn/bsma Wireless communication via electromagnetic trans- mission in the microwave range has become ubiq- uitous. In parallel, electronic devices are becoming 6.1.1 Functional Nanomaterials and more compact. These trends generate a growing Nanodevices issue with electromagnetic interference with con- sequences ranging from annoying to dangerous. Website: https://uclouvain.be/en/research- Classical EM radiation is shielded by Faraday cages institutes/imcn/bsma/functional-nanomaterials- which reflect the signal. By contrast, EM absorbers andnanodevices. html are more attractive because they truly eliminate the bothersome EM wav The ability to selectively arrange nanosized do- mains of inorganic and/or organic materials into hybrid nanomaterials offers an attractive route to 6.1.5 Ferromagnetic Nanowire Substrates engineer new nanostructured materials that can be for RF Electronics used in (spin) electronics, energy, memory and mi- crowave devices, catalysis, sensor and bio-medical. Ferromagnetic nanowires embedded into porous The BSMA division has expertise in the develop- templates are an interesting alternative route to ment of synthesis methods (nano imprinting, elec- ferrite-based materials. Over the last decade, the tro deposition in nano porous templates, thin-film groups at UCL have successfully prepared a variety deposition, nano assembly) to control the composi- of ferromagnetic nanowire substrates to design var- tion and shape of such hybrid nanostructures. ious prototypes of microwave devices, such as or circulators, isolators and phase shifters useful for wireless communication and automotive systems.

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6.1.6 Nanomagnetism in Nanoparticle photons and ions to nanoscale devices, through Arrays the crystalline state and molecules. The following topics are studied. Arrays of magnetic nanowires and nanotubes em- bedded in non-magnetic dielectric templates are of 6.2.1 Spectroscopy and Optics considerable interest for fundamental studies and for their exploitations in applications such as pat- The expertise in applied optics comes from the de- terned media for magnetic storage, microwave and velopment of laser techniques for fundamental re- spintronics devices. Control and tuning of their search in atomic physics. Progressively, this activity magnetic properties requires further understanding has focused on questions driven by industrial ap- of the interplay between intrinsic and shape effects plications. Today the activities are grouped in four as well as interaction among individual nanostruc- research topics. tures. Magneto elastic effects provide an additional parameter to control the magnetic properties be- • Optical properties of bio-inspired nanostruc- cause of the large surface area between nanowires tures and host matrix. • Optical characterization: coherence tomogra- phy, electro-optic sampling, deflectometry 6.1.7 Spintronics in Magnetic Nanowires • Laser generation of fast ions The template-based strategy has been successfully developed to fabricate arrays of magnetic multilay- • First-principles study of optical functional ma- ered nanowires. The nanowires system has pro- terials vided an important opportunity in exploring giant magnetoresistance effects in the current perpendic- 6.2.2 Light-matter Interaction ular to the planes geometry and in testing theo- retical models in various limits. Extensive giant The following activities are related to condensed magnetoresistance measurements were performed matter physics and magnetism. on various nanometer-scale multilayer structures, • Development of algorithms for numerical res- such as ColCu and NiFe/Cu nanowires. olution of Schrödinger equation

6.1.8 Template Free Electro Deposition of • Attosecond control of magnetism with an ultra Nano Rod Arrays and Devices short electromagnetic pulse at the atomic scale

The fabrication and characterization of ZnO • Study of interaction of atoms with super in- nanowires is the subject of intensive research in, tense field of low frequency due to their potential applications in highly inte- • First-principles study of optical functional ma- grated nanoscale electronic and optoelectronic cir- terials cuits with improved performance for solid-state dis- play devices, sensors, solar cells, energy harvesting devices, switchable hydrophobic surfaces, ... 6.2.3 Numerical simulation at the nanoscale 6.2 Research Division ”Nanoscopic The following activities are related to condensed Physics” (NAPS) matter physics and magnetism. • First-principles study of optical functional ma- Website: https://uclouvain.be/en/research- terials; materials for nanoelectronics; carbon- institutes/imcn/naps based nanostructures

At the nanoscale quantum mechanics plays a promi- • Ab initio quantum transport in nanostructures nent role, both for experimental investigations and theoretical simulations. The researchers in NAPS • STM imaging: experiments and ab initio mod- explore various aspects of this world, from atoms, eling

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6.2.4 Electronic transport at the nanoscale 7.2 The laboratory ”Physics of Functional Materials, The research activities are focused on transport properties imaging. Nanostructures and Biological Systems” (FunMat) • Ab initio quantum transport in nanostructures Website: http://www.facsc.ulg.ac.be/cms/c_950345/ • STM imaging: experiments and ab initio mod- pole-de-recherches-materiaux eling The FunMat laboratory performs research in the field of functional materials, in particular semi- • Imaging electronic transport at the nanoscale conductors, thermoelectrics, ferroelectrics, piezo- electrics, multiferroics, superconductors, and bio- • Quantum transport in low-dimensional sys- logical systems. The objective is to understand the tems behavior of matter at the atomic, molecular, and mesoscopic length scales. The unit is structured in five complementary subgroups with theoretical and 7 University of Liege` experimental competencies: i) physics of materials and nanostructures, ii) theoretical materials physics, 7.1 The Pole ”Soft Matter and iii) biomedical spectroscopy, iv) physics of solids, Complex Systems” interfaces, and nanostructures, and v) experimental physics ofnanostructured materials. Website: http://www.facsc.ulg.ac.be/cms/c_950347/ pole-de-recherches-matiere-molle 7.2.1 The Research Group ”Physics of Materials and Nanostructures The pole deals with the interactions between large (Nanomat) numbers of microscopic entities, which give rise to Website: http://www.nanomat.ulg.ac.be/ collective macroscopic phenomena. Experimental and numerical studies cover complex fluids, non- The Nanomat group investigates the electronic and linear systems, biophysics and statistical physics. vibration properties of materials for energy applica- Statistical physics creates a link between those mi- tions and novel generation electronics. The research croscopic features and the non-trivial macroscopic activities are concentrated on: - Thermoelectrics: behaviors. Soft matter refers to structured liq- materials, which couple differences in temperature uids, colloids, biological membranes, polymers, and electrical voltage. Applying a heat source to gels, foams, grains, and active materials. The group one side of a sample will induce a voltage across it, is equipped with instruments for microfluidics, rhe- or conversely by applying a voltage the sample can ology, imaging, laser spectroscopy. be used to cool one side or heat the other (solid state refrigerators/heaters with no compressors or mov- ing parts). The challenge is to understand the pro- 7.1.1 The Research Group for ”Research cesses, and to find materials which will allow these and Applications in Statistical principles to be scaled up to industrially useful de- Physics” (GRASP) vices. - Phonons and electron-phonon coupling: by inducing a deformation of the atomic structure, Website: http://grasp-lab.org/ the coupling between electrons and phonons gives rise to interesting phenomena such as supercon- The research projects are dedicated to the study of ductivity, normal resistivity, thermal resistance, or nanoparticles, suspensions, monolayers, biosensors, the Seebeck effect. Using ab initio tools one can self-assembling systems, powders, colloids, gran- calculate phonons and electron-phonon coupling to ular systems, droplets, antibubbles, microfluidics, good precision. - Attosecond dynamics: of electrons soap films, emulsions, foams, complex fluids, active and molecules poses serious challenges to both ex- matter, rheology, chaos and non-linear phenomena. periment and theory. The challenge is to come up

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with a unifying picture to understand the multi- the aim of unveiling new phenomena that are not ple configurations and trajectories of the density of present in large size systems. The main idea behind electrons, and especially to predict trajectories. structuring materials down to dimensions match- ing the characteristic sizes determining the physics 7.2.2 The Research Group ”Theoretical of the elementary blocks (i.e. electrons in metals, Material Physics” (TheMa) photons in dielectric media, plasmons at metallic interfaces, or fluxons in superconductors) is that Website: http://www.phythema.ulg.ac.be/ boundary conditions, surface effects, and interfaces become more relevant and lead to pronounced mod- The group is specialized in the first-principles mod- ifications of the general response of the system. The eling of multifunctional materials. This includes group is particularly interested in hybrid systems regular dielectrics, ferroelectrics, piezoelectrics, where the interplay of different physical mecha- magneto-electric multiferroics, thermoelectrics as nisms can lead to entirely new phenomena. well as materials for non-linear optical applica- tions. Recent works concerned the understand- ing of the evolution of the properties in various 8 University of Brussels types of nanostructures (ultra-thin films, superlat- tices, nanowires or nanoparticles) and the design of (ULB) artificial nanostructures with new and optimized properties. 8.1 The ”Laboratoire d’lnformation Quantique” (LIQ) 7.2.3 The Research Group ”Solid State Website: http://liq.ulb.ac.be/index.php?option= Physics: Interfaces and com_content&view=article&id=2&Itemid=2 Nanostructures” (SPIN)

Website: http://www.spin.ulg.ac.be/ Manipulating information at the quantum level is different from manipulating it classically. This The research activities of SPIN are dedicated to opens the door to some new and surprising appli- the study of the electrical and optical properties cations such as quantum cryptography or quantum of semiconducting materials and systems, with a computers. LIQ is actively working on different particular interest in crystalline ultra-thin films and aspects of quantum information. engineered nanostructures. The objective is focused • on the consequences related to intentional or non- Theoretical work: dealing with many aspects intentional atomic-scale variations of structure com- of quantum information, including quantum position, in terms of the impact on the electrical state estimation, quantum cloning, quantum activity, the crystalline quality of the deposited non-locality and communication complexity, nanostructures and of their interfaces. Experimen- quantum cryptography, and quantum coin tal techniques used are admittance spectroscopy, tossing. transient photoconductivity, absorption and photo- • The experimental quantum computing includes luminescence. the realization of an all fiber demonstration of algorithms, an all fiber demonstration of error 7.2.4 The Research Group ”Experimental filtration for quantum communication. Present Physics of Nanostructured Materials” work is focusing on the development of novel (EPNM) sources of entangled photons, both in fiber and in silicon waveguides. Website: http://www.mate.ulg.ac.be/

The research of EPNM is devoted to the investiga- 8.2 The Research Group ”Optique tion of confinement effects in mesoscopic systems Nonlinealre Theorique” (ONT) including nanomagnets, structured superconduc- tors, plasmonics, and hybrid heterostructures, with Website: http://www.ulb.ac.be/sciences/ont/

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The main field of application of the research done (OD, ID, 2D and 3D), the rational design of solids in the ONT group is optics. One of their speci- with specific architecture and surface properties, as ficities is the pursuit of analytical results, notably well as the development of advanced techniques through asymptotic methods. They are also ac- for the study of their physicochemical properties. tive in building mathematical models for optical An important role is played by the theoretical ap- systems. Current research themes are quantum proaches, through numerical simulation and mod- dots/dashes and their application in optoelectron- eling. The following topics are studied. ics; semiconductor lasers; laser mode locking: mod- eling and stability; transverse nonlinear effects: op- 9.1.1 Nonlinear Optics and Photonics tical structures in space or time; localized states and dissipative solitons; negative refraction index mate- Research is carried out in nonlinear optics (NLO), rials; micro-structured optical fibers; nonlinear me- quantum NLO, plasmonics, and photonics, applied dia and Bragg gratings; plasmons; nonlinear optics to multiscale structured matter (i.e. molecules, sur- in micro-cavities with whispering gallery modes; faces, biomaterials, nanomaterials, metamaterials, and solar cells. and crystals). Optical responses and their coupling to vibration and electronic excitations are predicted, from theoretical models using numerical simula- 8.3 The Research Group ”Physics tions, and measured, using dedicated experimental of Complex Systems and setups. Statistical Mechanics” 9.1.2 High Performance Computing (HPC) Website: http://complex.ulb.ac.be/ Multiscale Modeling

The research activities aim at understanding The HPC pole aims at 1) sharing computational complex phenomena on the basis of mathemat- techniques, skills and tools in order to develop new ical descriptions. The following research ac- materials and predict their final properties and 2) tivities are distinguished: fundamental aspects improving the modelling techniques and computer of complex systems, non-equilibrium thermody- codes to account for most of the chemistry and namics and stochastic processes, non-equilibrium physics of structured matter. statistical mechanics, classical transport from micro- to macro scale, complex quantum sys- 9.1.3 Functional Structured Materials tems, out-of-equilibrium nanosystems, in-and out- The expertise is divided in two areas: of-equilibrium surfaces, and multistep nucleation theory. • The development of 3D porous architectures including hierarchical organizations, MOF or MOF-like systems, organic/inorganic hybrids 9 University of Namur both using silica and carbon- based media, nanocomposites, etc. 9.1 The Namur Institute of • The functionalization of nanostructures such Structured Matter (NISM) as carbon nanotubes, fullerenes (C60), pillar- arenes, etc. The applications cover various Website: https://directory.unamur.be/entities/ topics including: Li-batteries, C02 conversion, nism?_LOCALE_=en biomass conversion, photosynthesis, (photo )catalysis, inhibition of viral and/or bacterial The research interests cover various topics in the pathogens, biomaterials, sensors ... field of organic and physical chemistry, materials chemistry, surface science, solid-state chemistry and 9.1.4 Surfaces, Interfaces and Carbon physics from both a theoretical and experimental Nanostructures point of view. It enables the exchange of ideas and competences in the field of synthesis and function- Synthesis, characterization and modeling of novel alization of molecular systems and novel materials materials, with particular attention to interfaces

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and to low-dimensional structures including carbon substrates, the other part is the synthesis of nanostructures (graphene, nanotubes). A choice of graphene by various techniques. The chemi- deposition and characterization methods is avail- cal modification of nano carbon materials is able. A theoretical support is provided to under- achieved, either by functionalization or post- stand 2D materials synthesis and growth, and to synthesis doping, using different techniques. interpret experimental data. The characterization of samples is realized by a variety of equipment. 9.2 The Research Center ”Physics • Theoretically: support is provided either to of Matter and Radiation (PMR)” understand graphene synthesis and growth mechanisms, or for the interpretation of exper- Website: http://pmr.unamur.be/fr imental data. Electronic structure calculations The researchers of the Department of Physics of are performed with both ab initio approaches the UNamur of are grouped under the banner "Re- and semi-empirical techniques. The quantum search Centre in Physics of Matter and Radiation" chemical design of carbon nanostructures re- (PMR). The research themes of the department deal lated to graphene, called nanographenes, is with the interaction between matter and radiation, studied for their remarkable optical properties. for instance, being linked to progress in materials, but also to developments in laser spectroscopy, the- oretical calculations and life sciences. Concerning 9.4 The Namur Center for Complex new materials PMR has developed a great exper- Systems (naXys) tise in the field of all types of thin film deposition (metallic, semiconductor, oxides, polymers, and Website: http://www.naxys.be/ biomolecules) by different physic-chemical tech- niques: sputtering, evaporation, epitaxy by molecu- Complex systems are composed of interacting lar beam or low-pressure cold plasma. These new parts/agents whose local behavior, resulting from materials are very often nanomaterials, with dom- the interactions, cannot provide a complete under- inant or quantic interface effects because of the standing of the global behavior. Several levels of de- nanometric scale of created objects. These effects scription!modeling of the system should be present give unique properties to materials. For example, at the same time: micro-meso-macro. This forces these nanomaterials are nanoparticles (functional- complex systems to be studied by trans disciplinary ized carbon nanotubes, nanocomposites combining teams, able to understand the whole construction two types of nanoparticles (carbon nanotubes and and critically analyze the connections among the metal), and bioinspired materials. description levels. This property is the result of a large number of elementary constituents and of the 9.3 The Research Group ”Carbon non-linearity of the interactions between them. Nanostructures” (Carbonnage)

Website: http://www.unamur.be/en/sci/ carbon- 10 University of Mons nage 10.1 The Research Group ”Micro- The group is active in the field of carbon nanostruc- tures (graphene, nanotubes, graphite, diamond-like and Nanophotonic Materials” carbon, etc.), which are studied both experimentally Website: www.umons.ac.be/nanophot and theoretically.

• Experimentally: the synthesis, functionalization Through numerical simulations and (semi- )ana- and characterization of carbon nanostructures lytical methods the group examines the behavior nanotubes and graphene) is studied. A part of light in structures with (sub- )wavelength scale of this research is dedicated to the synthe- elements. The following research subjects are con- sis of vertically aligned nanotubes on planar sidered:

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• Plasmonics: studying the coupling between physique_surfaces_interfaces/pages/default.aspx light and free electrons in a metal. They devel- oped a novel angle-optimized plasmonic struc- The goal of LPSI is to understand how the interfa- ture demonstrating better theoretical proper- cial characteristics of materials affect their function ties than ITO. The plasmonics research aims and performance, and hence determine their tech- to develop novel nanostructures for detectors, nological importance. The following subjects are optoelectronics or photovoltaics. studied:

• Graphene: The main goal of their graphene • Surface treatments: Minute compositional research is to understand the interactions be- changes can drastically modify the energetics tween light and graphene taking in account its and dynamics of interfaces. Interface science structural and doping defects and designing can therefore be a very efficient way of opti- original optoelectronic applications. mizing materials, in particular in areas such as microfluidics, where surface effects dominate. • Parity time symmetry: The similarity between the equations of quantum mechanics and op- • Surface and interface characterization: Research tics allows micro- and nano-photonics to test is concentrated on wet ability, coating, drying, of new non hermitic Hamiltonians. The goal friction and wear, lubrication, adhesion and ad- of the research is to adapt or create photonics hesives, optical properties. Modern techniques structures. are combined to explore material properties at various length scales.

10.2 The Research Institute for • Molecular modeling: Studies are based on the Materials Science and three complementary techniques of molecu- Engineering lar dynamics, Monte-Carlo simulations, and genetic algorithms. Specific modules address Website: http://portail.umons.ac.be/EN2/infossur/ collective properties such as viscosity, surface intranet/materiaux/Pages/default.aspx tension, and static and dynamic contact angles.

The institute combines the activities from three re- search centers: the Centre of Innovation and Re- 11 Conclusions search in Materials & Polymers (CIRMAP).; the Re- search Centre of Material Engineering (CRlM); and Condensed matter physics, including semiconduc- the Research Centre In Material Physics (CRPM, see tors, broadened its scope toward material science LPSI). and chemistry. The last thirty years the research CIRMAP studies the morphological, electronic, has been impressive by its permanent renewal optical, and transport properties of organic and it regularly produces major conceptual break- (semi)conducting materials in thin films. They de- throughs e.g. mesoscopic and nanostructured ma- termine the chemical nature, the structure, and terials, carbon-based materials, magnetic materials, the electronic properties of organic/organic and topological materials, dielectric and ferroic oxides, organic/inorganic interfaces. CRlM studies metals multiferroics, new superconductors, structures for and metal alloys, the electrochemistry of functional quantum computation, etc .. The importance is sup- ceramics, glasses and cements; heterogeneous catal- ported by the variety of experimental tools avail- ysis and absorbents, geo materials, structures and able e.g. scanning probe microscopy, enhanced syn- construction materials. For this survey we consider chrotron and neutron spectroscopy, new electron only the activities of LPS. microscopes, free electron lasers, etc. Intelligent use of better performing computers produced a revolu- 10.2.1 The ”Laboratory of Physics of tion in theory. Surfaces and Interfaces (LPSI)” During the past years, university laboratories in Bel- gium have contributed substantially to state-of-the- Website: http://portail.umons.ac.be/en2/universite art scientific achievements. This involved research /facultes/fs/services/institut_physique/ exploiting the expertise in theory and experiment,

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and via active collaborative programs sharing this expertise amongst various groups.

Leuven, February 2018

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