annual report 2015 CONTENTS
1 3 Director's letter People 4 Letter from the Director 4–5 Principal Investigators 8–11 Perspectives Staff 12–14 2 Alumni 15 Deciding our future 18–19 About CQT Governing Board 16 Scientific Advisory Board 17 CQT at a glance 6–7
5 7 CQT news Education 8 News in brief 20–23 Scientists in training 38–39 Listings Science update 24 29 Putting a PhD to use 40–41 – Papers 42–49 6 Events 50 51 Projects in focus – Outreach 52–53 Capturing value from 30–31 Visitors 54–55 fundamental research Money Matters 56–57 A record quantum 32–33 Supporters 58 speed-up CQTians 59 Time keepers 34–35 Meet the quantum 36–37 bunny
On the cover This 360° view inside one of CQT's labs shows a setup Find us online built to study quantum matter. The red laser helps cool atoms close to -273°C. Atoms this cold no longer behave like particles but more like waves. The green laser controls the atoms for experiments to help us understand phenomena such as superconductivity and magnetism. This project is run by Kai Dieckmann's group. Photo Credit: Daniel K. L. Oi / CQT, National University of Singapore www.quantumlah.org facebook.com/quantumlah twitter.com/quantumlah gplus.to/quantumlah youtube.com/quantumblah Director's letter Do you like assessments, writing progress reports, endless statistics 1 on publications, impact factors and the like? Of course not. Nobody does, but, once you are given a licence to turn taxpayers' money into quantum technologies, it is only fair that you tell others what you did with that money. An International Review Panel convened in "I knew we were doing 2015 to assess CQT’s first seven years of operation reported that it well, but it is always was “impressed”. Needless to say, I knew we were doing well, but it is always nice to hear it from others, especially those who can offer nice to hear it from LETTER FROM impartial judgement and constructive criticism. The end result: CQT others, especially those will continue to receive core funding through to 2022. who can offer impartial THE DIRECTOR After hearing the good news, some of us went celebrating. I can only judgement and recall one CQTian, a beer-maker, quoting the Heineken Uncertainty constructive criticism.” Principle which says that "you can never be sure how many beers you had last night". Disclaimer: we are not sponsored by Heineken (some of us are partial to local Tiger) but if we were offered such sponsorship on good terms we would consider it. Humour aside, while going through the review process I realised that the 2022 horizon, six years away, is almost another era in this Talking about the commercial world, one of the major problems we rapidly moving field. So much progress has been made in the past will be facing in years to come is finding an optimal balance between six years (not necessarily in the directions we originally anticipated) basic and applied research. For some, basic research seems to that one can hardly speculate what will happen by then. Of course, be terribly inefficient and its practical results hard to predict. For I can stretch my imagination and suggest quantum random number others, myself included, it is the essence from which the practical generators in local casinos, island-wide quantum key distribution applications of knowledge is drawn. Both sides have arguments. I networks, quantum simulators which help to design new drugs, and believe CQT's strength is mostly in basic research, but we should super-precise atomic clocks leading to a super-accurate global certainly diversify our research and include more industry-related positioning system. But the thing is, each year brings surprises. projects in our portfolio. I am glad to say that this is already happening. Just this year our computers scientists surprised us, and the whole international community, by overturning a long-held belief that some Even though I cannot tell you what exactly we will be working on forms of quantum computation can admit only quadratic speed-up. six years from now, I do know that we will be doing something They showed that quartic speed-up is possible (see pp. 32–33). interesting. I can say this with some degree of certainty because I This can open new directions for research. How could we possibly see genuine quality and potential in our team. I must stress that the have foreseen this development a few years ago? We could not. And team means not just academic researchers but literally everyone at there are other surprises as well. For example, we were genuinely CQT. This report will tell you more about our people and the many surprised when we learned that the explosion that destroyed the things they have achieved in 2015. I hope you will like it. Antares rocket carrying our payload did not destroy CQT's Small Photon-Entangling Quantum System (see p. 25). So, dear industrial partners and colleagues out there in the commercial world, if you are after truly robust quantum technology, look no further, talk to us!
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Centre for Quantum Technologies I Annual Report 2015 About CQT In 2015 CQT researchers 2 published more than 150 papers. The chart shows CQT’s cumulative research output since the 1400 Centre was established. 1200 1000 CQT AT 800 600
400 A GLANCE 200 0 The Centre for Quantum Technologies brings together quantum 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 physicists and computer scientists to conduct interdisciplinary Staff numbers research into the foundations of quantum theory and the ways quantum physics enables new technologies. CQT was established Admin Research in December 2007 as Singapore’s inaugural Research Centre of staff support Excellence with support from the National Research Foundation and Principal 19 7 Investigators Ministry of Education. 20 PhD students 56 53 Research < CQT is hosted at the National University staff 18 of Singapore (pictured). The Centre CQT research covers a broad range also has staff and facilities at Nanyang of topics. We are developing tools Technological University. Visiting staff to control the behaviour of individual particles of matter and light – atoms Total 173, snapshot at 31 December 2015 and photons. Harnessing quantum phenomena at this scale can enable technologies that you would Budget overview 2015 think impossible – from incredibly precise clocks (see pp. 34–35) to the speeding up of computation Equipment (see pp. 32–33). 2,007,648 Manpower
9,841,471 5,951,837
Other Explore more highlights of our published Operating Expenditure research on pages 24–29. Learn more at quantumlah.org/research 6 7
Centre for Quantum Technologies I Annual Report 2015 < Murray Barrett People 3 Experimental Physics Other appointments: Associate Professor, Department of Physics, National University of
Singapore <
Manas Mukherjee Kai Dieckmann < Experimental Physics Experimental Physics
Other appointments: Other appointments: Assistant Professor, Associate Professor, A "unique feature of the CQT Department of Physics, Department of Physics, PRINCIPAL National University of National University of PIs is the team spirit and the Singapore Singapore dynamism that is necessary INVESTIGATORS for identifying and venturing into new experimental research directions" < Alexander Ling < Christian Kurtsiefer < Dzmitry Matsukevich Experimental Physics Experimental Physics Experimental Physics International Review Panel, 2015 Other appointments: Other appointments: Other appointments: Assistant Professor, Professor, Department Assistant Professor, Department of Physics, of Physics, National Department of Physics, National University of University of Singapore National University of Singapore
Singapore
< <
Björn Hessmo < Rainer Dumke Wenhui Li Experimental Physics Experimental Physics Experimental Physics
Other appointments: Other appointments: Other appointments: Assistant Professor, Associate Professor, School Assistant Professor, Department of Physics, of Physical & Mathematical Department of Physics, National University of Sciences, Nanyang National University of Singapore Technological University, Singapore Singapore
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Centre for Quantum Technologies I Annual Report 2015 < Miklos Santha People 3 Computer Science Other appointments: Senior Researcher at CNRS in the Laboratoire d'Informatique Algorithmique: Fondements et Applications at the University Paris Diderot,
France
< <
Stephanie Wehner Troy Lee < Computer Science Computer Science
Other appointments: Other appointments: Associate Professor, QuTech, Associate Professor, School Delft University of Technology of Physical & Mathematical PRINCIPAL Sciences, Nanyang Technological University, INVESTIGATORS Singapore
< Leong Chuan Kwek < Hartmut Klauck < Valerio Scarani Theoretical Physics < Dimitris G. Angelakis Computer Science Theoretical Physics Theoretical Physics Other appointments: Other appointments: Other appointments: Associate Professor, Other appointments: Assistant Professor, School Professor, Department of National Institute of Assistant Professor, School of Physical & Mathematical Physics, National University Education and Deputy of Electronic and Computer Sciences, Nanyang of Singapore Director, Institute of Engineering, Technical Technological University, Advanced Studies, Nanyang University of Crete, Greece Singapore Technological University,
Singapore
< < < <
Dagomir Kaszlikowski Vlatko Vedral Berthold-Georg Englert < Rahul Jain Theoretical Physics Theoretical Physics Theoretical Physics Computer Science
Other appointments: Other appointments: Other appointments: Other appointments: Associate Professor, Professor, Department of Professor, Department of Associate Professor, Department of Physics, Physics, National University Physics, National University of Department of Computer National University of of Singapore and Professor, Singapore Science, National University Singapore University of Oxford, UK of Singapore
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Centre for Quantum Technologies I Annual Report 2015 3 People Research Assistants Senior Research Fellows
Andrew Bah Shen Jing Nelly Ng Huei Ying Benny Joakim Andersson Attila Pereszlenski Nguyen Thi Phuc Tan Gleb Maslennikov Brigitta Septriani Noah Van Horne Itai Arad Do Thi Xuan Hung Oon Fong En Martin Rudolf Kiffner Elnur Hajiyev Pramod Mysore Srinivas Noh Chang Suk Ew Chee Howe Ritayan Roy Paul Constantine Condylis Gan Koon Siang Robert Pisarczyk Pawel Krzysztof Kurzynski Guan Yilun Shalima Binta Manir Thibault Thomas Vogt Gupreet Kaur Gulati Shi Yicheng Yu Sixia STAFF Kwong Chang Jian Tan Peng Kian Lee Chern Hui Tan Yue Chuan Leong Xu Heng Victor Thi Ha Kyaw Ley Li Yuan Vindhiya Prakash Musawwadah Mukhtar Yau Yong Sean Research PhD Students Associates
Aarthi Meenakshi Sundaram Jedrzej Kaniewski Supartha Podder Aarthi Lavanya Dhanapaul Aitor Villar Zafra Jiabin You Swarup Das Cheng Too Kee Alessandro Landra Jirawat Tangpanitanon Tang Zhongkan Kamiyuki Xavier Chng Mei Yuen, Brenda Alexandre Roulet Jungjun Park Tarun Dutta Research Fellows Truong-Dzuy Edward Truong-Cao Anurag Anshu Le Phuc Thinh Thi Ha Kyaw Aram Mikaelyan Lee Jianwei Ulrike Bornheimer Alessandro Cere Markus Debatin Bharath Srivathsan Len Yink Loong Vamsi Krishna Devabathini Andrew James Philip Garner Markus Philipp Baden Cai Yu Li Xikun Ved Prakash Cai Yu Maria Martinez Valado Chai Jing Hao Lim Chin Chean Victor Javier Huarcaya Azanon Chia Andy Hsiao-Li Michal Hajdusek Chi Huan Nguyen Maharshi Ray Wei Nie Christoph Hufnagel Michele Dall'Arno Christian Gross Manan Jain Wilson Yue Sum Chin Dai Jibo Mischa Woods Corsin Pfister Marek Wajs Wu Xingyao Guo Ruixiang Mohamed Riadh Rebhi Dai Jibo Mathias Alexander Seidler Ye Luyao Han Rui Nicholas Charles Lewty CQT Debashis De Munshi Mun Choong Mark Lam Zhang Zhiqiang James Anthony Grieve Poh Hou Shun Fellows Ding Shiqian Naveinah Chandrasekaran Jamie William Jonathon Sikora Robert Bedington Davit Aghamalyan Poh Hou Shun Jean-Daniel Bancal Sai Vinjanampathy Oh Choo Hiap Eduardo Javier Paez Barrios Priyanka Mukhopadhyay Kadir Durak Saptarishi Chaudhuri Benoit Gremaud Ewan Munro Rakhitha Chandrasekara Kanhaiya Pandey Shabnam Safaei Filip Auksztol Rattakorn Kaewuam Kyle Joseph Arnold Shang Jiangwei Assistant Francesca Tosto Ritayan Roy Laura Mancinska Tan Kok Chuan Bobby Professor Frederic Leroux Roland Hablutzel Le Huy Nguyen Jayne Elizabeth Donovan Thompson Goh Koon Tong Sambit Bikas Pal Lee Changhyub Tomos Harry Johnson Ng Hui Khoon Gurpreet Kaur Gulati Sanjib Ghosh Lee Su-Yong Trappe Martin-Isbjoern Han Jingshan Seah Yi-Lin Loh Huanqian Yu Deshui Hermanni Heimonen See Tian Feng Ma Ping Nang Hu Yu-Xin Sim Jun Yan Jaren Gan Suen Whei Yeap
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Centre for Quantum Technologies I Annual Report 2015 People 3 Research Support Type of job
Akimov Volodymr Chia Zhi Neng Bob ALUMNI Visiting Senior Gan Eng Swee Academic Visiting Research Research Fellows Lian Chorng Wang Professors Mohd Imran Bin Abdol Raman The CQT research community is constantly renewing itself as students 87% Chen Jingling Radhakrishnan Nair Dileej graduate and postdocs move on. By the end of 2015, the Centre had Dieter Hans Jaksch Dmitry Gavinsky Ren Yaping 223 academic alumni. The data presented here are collected from 97 Ghassan Georges Batrouni Mile Gu Teo Kok Seng John Carlos Baez Thomas Georges Pierre Vidick responses to a survey of our former CQTians. 5% Joannes Theodorus Maria Walraven Venkatesh Srinivasan Jose Ignacio Latorre 8% Luigi Amico Masahito Hayashi Science-related Administrative Staff industry Miniatura Christian Pierre-Marie Other Rosario Fazio Visiting Artur Ekert Lim Mei Yin, Valerie Thomas Francis Gallagher Research Chan Chui Theng Lim Mui Lian, Amell Fellow Chin Pei Pei Mashitah Bte Mohammad Moasi Giam Lay Enn, Kelly Norima Bte Mohamat Sarnon Top ten destinations Tristan Farrow Jenny Hogan Poovathumkal Raju Resmi Visiting Research Jessie Ho Tan Ai Leng, Irene Associate Kuldip Singh Tan Hui Min Evon Professors Lai Choy Heng Tan Lay Hua 16 Lim Ah Bee Valerie Hoon Antia Lamas Linares Research LKY Lim Fang Eng Jacky Yeo Kwan San Timothy David Paul Maxime Wilkowski 14 David Andrew Wilson Hutchinson Assistant Postdoctoral Gabor Ivanyos Professors Fellow 12 Joseph Fitzsimons Matthias Steiner Tomasz Paterek 10 Read interviews with some recent graduates 8 of our PhD programme on pages 40–41. 6
4
2
0 Sinagpore UK China USA Australia Germany Korea India Canada Spain
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Centre for Quantum Technologies I Annual Report 2015 3 People
SCIENTIFIC GOVERNING ADVISORY BOARD BOARD < The SAB makes an annual visit to CQT to Lam Chuan Leong (Chairman) Artur Ekert Lui Pao Chuen Ignacio Cirac Christophe Salomon talk science. Here Gerard Milburn (right) • Senior Fellow, Lee Kuan Yew School of Public • Director, Centre for Quantum Technologies • Advisor, National Research Foundation • Director, Head of Theory Division, Max- • Research Director, Laboratoire Kastler is in conversation with CQT Principal Policy, National University of Singapore • Lee Kong Chian Centennial Professor, Planck Institute of Quantum Optics Brossel, CNRS Investigator Berge Englert (left). • Director, ST Electronics (Info-Software) National University of Singapore Tan Eng Chye Systems Pte Ltd • Professor of Quantum Physics, • Deputy President (Academic Affairs) and Atac Imamoglu Umesh Vazirani University of Oxford Provost, National University of Singapore • Head of Research, Quantum Photonics • Director, Berkeley Quantum Computation Serguei Beloussov Group, Institute of Quantum Electronics, Center (BQIC), Computer Science Division, • CEO, Acronis Ho Teck Hua Tan Geok Leng ETH Zurich College of Engineering, UC Berkeley • Senior Founding Partner, Quantum Wave • Tan Chin Tuan Centennial Professor • Executive Director, Science and Engineering Capital and Deputy President (Research and Research Council, A*STAR Gerard Milburn Jun Ye • Founding Partner, Runa Capital Technology), National University of • Director, Centre for Engineered Quantum • JILA and NIST Fellow, University of Colorado • Chairman of the Board and Chief Architect, Singapore Systems, University of Queensland and National Institute of Standards and Parallels Technology • Chairman of the Board of Trustees, Russian John Lim Michele Mosca Quantum Centre • Divisional Director, Higher Education Policy • Deputy Director and Co-founder, Institute Division and Divisional Director, Higher of Quantum Computing, University of Nicholas Bigelow Education Operations Division, Ministry of Waterloo Changes to the Governing • Professor of Optics, The Institute of Optics, Education Board in January 2015 University of Rochester Lee May Gee (Alternate member) Ho Teck Hua replaced Chang Yew Kong • Deputy Director (Higher Education), Barry Halliwell, Tan • President, ST Electronics Software Systems Ministry of Education Chin Tuan Centennial Group George Loh Professor and Senior Advisor to the President, • Director, Physical Sciences & Engineering NUS Directorate, National Research Foundation
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Centre for Quantum Technologies I Annual Report 2015 4 Perspectives On Doctors’ Advice The members of CQT’s Scientific Advisory Board (SAB) made their annual visit to the Centre in July. In a report submitted to CQT’s DECIDING Governing Board and Principal Investigators, the SAB writes “As the Centre had completed a major external review just prior to the meeting of the SAB, we have taken this opportunity to take a more strategic view OUR FUTURE of the Centre’s research program and general operations.” CQT went through two reviews in 2015 An International Review Panel (IRP) convened in 2015 to assess CQT’s Details of the support to come from the Centre’s major The report outlines the big picture, noting that CQT “is now planning for first seven years of operation reported that it was “impressed”. stakeholders – MOE, the National Research Foundation (NRF) the next phase of operation beyond 2017… The Centre should continue The IRP conducted an external evaluation of the Centre arranged Singapore and our host university, the National University of to seek targets of opportunity to ensure that it remains a global leader in by Singapore’s Ministry of Education (MOE) “to provide a critical Singapore – will be confirmed in 2016. fundamental quantum science.” assessment of CQT’s performance, strategic relevance and future potential.” As well as welcoming the IRP in April, the Centre hosted its The report also presents a set of recommendations for the Centre Scientific Advisory Board in July. The scientists on the board made spanning funding, staffing and facilities. These include the suggestions The IRP’s report (see box below) formed one input to the Academic strategic recommendations for changes that could strengthen that “every PI has at least one external grant, either held individually Research Council that advises on the spending of Singapore’s CQT (see box to right). or in collaboration with another PI” and that “the Centre establish an research budget. We were pleased to learn following the meeting of internal PhD research workshop run by the PhD students themselves. this council that CQT will continue to receive core funding through We are grateful to the many people involved in organising and This should include an event to encourage experimental students to to 2022. Initial grants to the Centre were to fund its first ten years of carrying out these assessments for their careful help in shaping visit other laboratories.” operation, until the end of 2017. CQT's future.
Objective Perspective class researchers, both senior and junior, established a strong Members of the IRP, 2015 At the invitation of Singapore's Ministry of Education, eminent relationship with local Universities and built the requisite infrastructure scientists joined an International Review Panel (IRP) to help assess Raymond Laflamme (Chair) Atac Imamoglu to support the Centre. These elements culminated in making a strong Director, Institute of Quantum Computing, University of (Ex-officio Member, CQT SAB) the performance of CQT. The members of the IRP received a self- scientific impact in the international community and built a reputation Waterloo Head of Institute for Quantum Electronics, ETH Zurich assessment report from the Centre and spent four days in Singapore of excellence for Singapore.” in April for meetings with staff and stakeholders. The IRP was asked to Gerd Leuchs Observer: focus first and foremost on assessing CQT’s quality of research and Considering the Centre’s long term potential, the IRP wrote “Quantum Director, Max Planck Institute for the Science of Light Nicholas Bigelow organisation, followed by its success in talent development. science is an unusually dynamic field with frequent ground-breaking (Representative of MOE’s Academic Research Council, CQT GB) Andrew Yao Lee A. DuBridge Professor of Physics & Optics, University of developments on both sides, theory and experiment. CQT has Dean, Institute for Interdisciplinary Information Sciences, Rochester The panel summarized its report as follows: “The International Review emerged as a major player in this field, with a potential to influence its Tsinghua University Panel has been impressed by the achievements of the Centre for future trajectory.” Quantum Technologies. In a short time span, it has attracted world-
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Centre for Quantum Technologies I Annual Report 2015 CQT news Co-organised a UK-Singapore 5 Quantum Symposium The Symposium held 26–27 March at NUS brought together leading researchers in quantum technologies from the UK and NEWS IN BRIEF Singapore. Both countries have made long- Got inspired at the theatre term investments in quantum tech: Singapore in What we did this year... The CQT writer’s residency of Singaporean playwright CQT and the UK in the 2013 announcement of Eleanor Wong culminated in March in two evenings of a national Quantum Technologies Programme performance at Centre 42 theatre. Drawing inspiration worth £270 million. The meeting’s goals were from ideas and themes in the quantum world to to foster the exchange of ideas and spark inform and illumine ordinary life, Initial Conditions was collaborations. The event was organised Applauded our two APS Fellows presented as a staged reading by Cake Theatrical by CQT and the British High Commission's Two of CQT's founding members, Professors Oh Productions with support from Centre 42. The piece Science and Innovation team. Choo Hiap and Berge Englert, were elected Fellows will become part of a larger meditation on love and of the American Physical Society in 2015. The relationships in a changing world. Eleanor gathered society has some 51,000 members around the world, material for her work over four months in 2014 through with fellowship limited to no more than 0.5% of this meetings with scientists, lab visits and attending talks. number. Choo Hiap (pictured right) was cited "For vital contributions to the development of physics teaching The Quantum Immersion writer’s residency is Exhibited all over town and research in Singapore, especially establishing its supported by Singapore’s National Arts Council. CQT There were many opportunities for the public to meet leading position in research in quantum technology, welcomed Tania De Rozario as the Centre's writer-in- us this year. CQT's research in quantum cryptography and for important personal contributions to this field." residence for 2015 in September. was featured in the NUS exhibition "Building Our Nation Berge (left) was cited "For distinctive theoretical through Science and Technology" on campus and contributions to the foundations, interpretation, and in shopping malls. We also took hands-on setups to applications of quantum mechanics." Xperiment, the opening event of the Singapore Science Festival. Held at VivoCity mall, the three-day event is estimated to have attracted 35,000 people. Last but not least, CQT organised a one-day showcase at Singapore’s ArtScience museum in December, offering seven zones of exhibits including experiments and film screenings. Some 400 people visited. “Even my 5 year old enjoyed it. The presenters did a good job explaining on her level,” wrote one visitor on their feedback form.
Photo Credit: Tuckys Photography
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Centre for Quantum Technologies I Annual Report 2015 CQT news Hosted the International Conference on 5 Laser Spectroscopy Some 240 scientists, students and exhibitors from 25 countries came to Singapore for ICOLS 2015, a prestigious biennial conference in atomic, molecular and optical physics. The conference was held 28 June to 3 July at the Shangri-La Rasa Resort on Sentosa island. "We had great talks on topics ranging from a new quantum authentication protocol to the extreme precision of atomic clocks and research on optical activation of neurons. Awarded film prizes The ambience of the venue was also very nice," said Kai The Quantum Shorts contest that launched in 2014 Dieckmann, CQT Principal Investigator and chair of the reached its conclusion in April, with prizes awarded organising committee. Launched Generation Q Camp to a handful of quantum-inspired movies under Thirteen students from eight Singapore junior three minutes long. Top prize went to UK-based The next major international conference to be hosted by colleges attended Generation Q Camp, an artists Ruth Jarman and Joe Gerhardt, known as CQT is the 13th International Conference on Quantum intensive three-day workshop at CQT in June. Semiconductor, for a visualization of data captured Computing, Measurement and Communication, to be held Organiser Jamie Sikora, a Research Fellow, during a geomagnetic storm in the Earth's upper at NUS University Town 4–8 July 2016. said "I wanted to introduce young students atmosphere. Judge Charlotte Stoddart, head of to the exciting worlds of quantum physics, Multimedia at Nature, said "20Hz is a beautiful and advanced mathematics and cryptography. The mesmerising film." Nature and Scientific American Congratulated our young innovator goal of the camp is to give a quick glimpse were media partners for the 2014 contest. We CQT's Joe Fitzsimons, who does research on the of quantum cryptography, explain why it's launched a new Quantum Shorts contest for flash theory of quantum computing, was one of ten secure, and how such devices are being fiction in September, teaming up with quantum scientists and entrepreneurs selected for the 2016 MIT built today." One participant said the camp centres around the world as scientific partners. Technology Review's 'Innovators Under 35 Asia' list. He had "made quantum mechanics much more is best known for being a co-inventor of blind quantum appealing and exciting to me". computing, a protocol to delegate a computation to a remote quantum computer while keeping the description of the computation hidden from the device Graduated PhD students executing it. Eight CQT PhD students were formally awarded their doctoral degrees at the Joe is a Research Assistant Professor with CQT and NUS commencement ceremony on 9 an Assistant Professor at the Singapore University of July. "It has been, and continues to be, a Technology and Design. He was awarded a National privilege to have all these talented young Research Foundation Fellowship in 2013. people in our PhD@CQT programme," says Berge Englert, head of CQT's Academic Committee. Including this year's cohort, CQT has seen a total of 25 students graduate since its programme was established in 2007.
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Centre for Quantum Technologies I Annual Report 2015 5 CQT news
Experiment survives rocket explosion SCIENCE UPDATES CQT’s first satellite payload – a quantum photon source – survived being in a rocket that failed on launch, Highlights of our published research.... disintegrating in a giant ball of fire. "We don't know how the device survived the explosion, but this has validated the years of careful design that was put into the project," CQT researcher Alexander Ling told the Straits Times Photons shape up newspaper, which covered the news in August. The device CQT’s quantum mechanics demonstrated an was a first generation of the Small Photon-Entangling elegant trick to shape photons to be more Boost for interactive proofs Quantum System (SPEQS), intended to test technology for a easily absorbed by atoms (Physical Review A big question for researchers in quantum computing is, global quantum communication network. Letters 113, 163601). The technique could where does quantum physics give an advantage? CQT be used in devices that shuttle information researcher Joe Fitzsimons and his collaborator have The group will not reuse the recovered device but have between photons and atoms and back again. added to the list with a “multiprover interactive proof written up the post-explosion test results for publication Christian Kurtsiefer and his team first created system" that gains power by exploiting entanglement. The (preprint at arXiv:1512.08834). They also have new a pair of correlated photons, then engineered findings were presented at conferences in 2015 (preprint at generations of the device ready for the next attempt to the shape of one by operating on the other. arXiv:1409.0260). reach orbit. Their goal was a photon of exponentially rising brightness. A cold cloud of Rubidium atoms An interactive proof is when the verifier can question a more (pictured) create the photons. powerful but untrustworthy ‘prover’. Computer scientists know that you can check a wider range of proofs with access to this kind of help than you can without, and that if you add more provers you can do better still. The discovery that you can verify even more from entangled provers was, however, unexpected because people had thought provers might use entanglement to cheat.
Photo Credit: NASA / Joel Kowsky
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Centre for Quantum Technologies I Annual Report 2015 5 CQT news Computing with time travel A message sent back in time could help us to perform currently intractable computations – even if that message is never read, according to work by CQT’s Mile Gu (npj Quantum Information 1, 15007) and his Calling on entanglement witnesses collaborators. Researchers had previously found that In a collaboration with Singapore’s Data Storage Institute, Two mysteries become one messages sent into the past along closed timelike Wave-particle duality and uncertainty have been Berge Englert’s group demonstrated an improved curves could gain computational power, but physicists scheme for detecting entanglement, which is the property fundamental concepts in quantum physics since dislike closed timelike curves because they violate the early 1900s – now we know they are different of two particles existing in a shared state. Entanglement causality. The classic example is that someone could is an essential ingredient for quantum protocols in manifestations of the same thing. This is thanks to work travel back in time and kill their grandfather, negating by an international team led by Stephanie Wehner communication and computation, making an ability to test their own existence. The team's new scheme sidesteps for it important. (Nature Communications 5, 5814). this issue by using open timelike curves that don’t allow any interaction with the past. They showed that Previously it was thought that you would need as many The quantum uncertainty principle sets a limit on how there is still a gain in computational power as long as precisely you can know certain pairs of a particle’s as 15 witness measurements to be sure that two qubits Introducing the quantacell the time-travelling particle is entangled with one kept were entangled. The new scheme needs at most six properties at once. Stephanie’s team found that in the present. knowledge about the wave versus particle behaviour of "The authors hope that this article will inspire Tesla Motors measurements and a mean of only 2.5, when the to start developing quantum batteries for their vehicles". witnesses are chosen carefully (Physical Review Letters a system is constrained in exactly the same way. They 113 used the language of entropic uncertainty relations to That small note comes at the end of a theoretical paper , 170402). The tests were performed on photon pairs, make the connection. by CQT’s Sai Vinjamapathy and co-authors proposing that assuming the source produces identical pairs each time. quantum batteries could charge faster than classical ones (New Journal of Physics 17, 075015). The imagined battery is made from an array of particles, each of which can be 'charged' by absorbing energy to go from a lower to a higher energy state. The researchers find that the time it takes to charge N particles can scale as 1/N – in other words, the bigger the battery, the faster it charges. The speed-up is possible because entanglement is created between the particles. The best you'd expect without entanglement is a constant charging time.
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Centre for Quantum Technologies I Annual Report 2015 5 CQT news Extreme quantum weirdness CQT researchers observed the most extreme quantum weirdness ever measured in the lab. The precision measurement of entanglement in photon Precision with Barium pairs by Christian Kurtsiefer’s group pushed close Manas Mukherjee’s group at CQT measured to Tsirelson’s bound – the quantum limit for the Bell properties of Barium ions with record precision test they performed. The achievement is evidence Majoranon simulation (Physical Review A 91, 040501). The results are for the validity of quantum physics and will bolster An experiment brought into virtual existence an impossible relevant to the search for physics beyond the confidence in schemes for quantum cryptography particle known as a “Majoranon” (Optica 4, 454). The work Standard Model because Barium is a strong and quantum computing designed to exploit this involving CQT theorist Dimitris Angelakis was proof-of- candidate for studies of parity violation. phenomenon. Coauthored with a theorist from the principle that quantum simulation techniques can explore University of Seville in Spain, the paper (Physical the boundaries of known physics. Dimitris’ team had earlier The team measured transition probabilities and Review Letters 115, 180408) reports that the proposed a way to simulate the famous Majorana equation, branching fractions for 138Ba+ from an excited p-state measurement also rules out a proposed extension to which has two solutions representing different types of to lower energy s and d states. Their findings were quantum theory. particles. One solution is thought to describe neutrinos, in agreement with but up to six times more precise The second laws of quantum chargeless particles that interact so weakly with matter than the previous best experimental results. The thermodynamics that you don't notice the billions of them streaming through you every minute. The other solution is the ‘Majoranon’, data constrains theoretical predictions which vary The second law of thermodynamics says that because they depend on simplifying assumptions. presumed not to exist because it would violate the law of entropy will increase, describing things as diverse charge conservation. This forbidden physics was possible in as the cooling of a cup of coffee, the efficiency of the simulation, however, performed in Germany with light in a engines and the heat death of the Universe. Now waveguide chip. researchers including CQT's Stephanie Wehner have shown that the classical second law has a family of cousins operating at smaller scales (PNAS 112, 3275). The discovery of these second laws of quantum thermodynamics will be important to understanding the behaviour of quantum systems and nanomachines. The new laws converge to the traditional one when applied to large systems.
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Centre for Quantum Technologies I Annual Report 2015 6 Projects in focus CAPTURING VALUE FROM CQT benefits from doing outreach to industry too. We are gaining new FUNDAMENTAL RESEARCH perspectives on how to frame our research questions and deeper CQT can offer technology, advice and skilled manpower to local business and insight into the problems industry and agencies want to solve. Our meetings are often a two-way exchange of ideas. government writes Alexander Ling, who leads the Centre’s outreach to industry Open conversation may be the way we discover value in the ‘collateral’ In 2015, researchers from CQT held a record number of meetings with With growing global interest in the commercial potential of quantum outcomes of fundamental research. To build experiments that push the representatives from industry and government agencies. We hosted technologies, from the precision sensors of today to the quantum forefront of human knowledge, scientists often invent new technologies delegations in our laboratories and participated in events such as computers of the future, we see CQT having an important local role to to help. These technologies are not the goal of the research but side- the “R&D Showcase to Large Local Enterprises (LLEs)” organised by play. We aim to deliver value from our research in three ways: through products. Singapore’s National Research Foundation in July. innovation, by providing advice and as a source of skilled people. In one presentation we gave about CQT technology for secure communication, for example, we described how we distribute a key using entangled photon pairs born within a few femtoseconds of each other. Our visitors were interested in whether the photon timing could As a As an As an be used to provide time-keeping without relying on an external service source of advisor innovator like the global positioning system (GPS). The idea had struck us too, manpower and we could point our visitors to a CQT paper about how this might work. As quantum devices reach technological CQT trains its researchers and students to CQT is exploring how to commercialise some We don’t know yet if this idea will be pursued commercially, but there maturity, industry is becoming more interested a high standard. We have created a core of its own technological innovations. Because is precedent for collateral discoveries to become big successes. A in how they work. Here CQT plays an important of people who could staff future technology CQT is primarily a basic science organisation famous example is the world wide web, first created by scientists at advisory role. CQT can keep local stakeholders businesses. To encourage innovation, we are looking to license our ideas or build the particle physics laboratory CERN to manage information about informed about how quantum technology can businesses need to employ active problem- partnerships to make this happen. We hope to their experiments. impact their operations. This includes knowing, solvers – and there’s no doubt that doing see joint projects emerging from our ongoing for example, how the prospect of a quantum research at CQT develops such skills. Giving conversations in the next few years. We will Businesses or agencies interested in collaborating with CQT or learning more about computer threatens public key encryption decision makers a first-hand look at our facilities also support any researchers who want to strike CQT research can contact Alexander Ling at [email protected] systems, or about the cutting-edge capabilities and research outcomes makes clear what our out on their own to form start-ups through the of single-photon detectors. We are preparing to graduates can do. University’s enterprise programmes. give workshops on high-interest topics.
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Centre for Quantum Technologies I Annual Report 2015 6 Projects in focus
A RECORD QUANTUM SPEED-UP Written D(f)~Q(f)2, it translates to a quadratically faster run-time for the An important point is that the speed-up record is only for total CQT Principal Investigators Troy Lee and Miklos Santha overturned a long- quantum algorithm. functions – ones that accept any input. There’s another famous quantum algorithm, Shor's algorithm for factoring, which has an held belief about what quantum algorithms can achieve The quadratic separation of Grover's algorithm has remained the best exponential speed-up. However, Shor’s is a partial function, meaning known separation for total functions since the algorithm was described that it is defined only for some inputs. This year CQT computer scientists and their collaborators busted a Query complexity is a measure of how much one needs to know about in 1996, despite intensive search for something better. Given this hypothetical ceiling on quantum speed-ups, the theoretical speediness the input of a function to determine the output. It comes in different situation, researchers thought Grover’s might have hit a limit. Complexity relationships of a quantum versus a classical program in solving a problem. flavours depending on what constraints you apply to how you access "It was really quite a deeply held belief in the community that a The researchers also set new records for the relationships between the input – including whether you can query in a quantum way – and if quadratic separation was the best possible," says Troy, who is also deterministic and randomised zero-error query complexity (refuting It was big news in the community. The results were greeted as a you must know the output with certainty or just with high probability. faculty at Nanyang Technological University. But the team’s work a conjecture that had stood since 1986), and zero-error and "breakthrough" on the widely-read blog Shtetl-Optimized by computer uprooted this belief, showing a function for which the quantum query 4 bounded-error randomized query complexities. Scott Aaronson and scientist Scott Aaronson at the Massachusetts Institute of Technology. Grover's algorithm famously has quantum query complexity that is complexity is a power of four better: D(f)~Q(f) . his coauthors have since built on these results, presenting findings He wrote "The highest compliment one researcher can pay another is, a power of two better than that of the classical query complexity. including a super-quadratic separation between quantum and 'I wish I'd found that myself.' And I do, of course, but having missed it, randomized query complexitiesii at QIP 2016. I'm thrilled that at least I get to be alive for it and blog about it. Huge < One of the promises of quantum computing is that we can solve iii congratulations to the authors!" problems faster, but how much faster? CQT researchers have CQT’s team initally set out to understand a paper which improved described a function with a record power-of-four quantum speed on earlier results by Miklos, also at the French national research Double powered up, overturning a long-held belief that you couldn't do better organisation CNRS. "So he was of course interested to see what they than quadratic for total functions. Whereas the previous best quantum advantage for ‘total functions’ was had done and see if he could improve it further," explains Troy. The the quadratic speed-up of Grover’s algorithm – for searching unsorted new work involves variants of a function defined in that paper. databases – the new speed-up is that squared: it’s quartic. The new ‘super Grover’ algorithm does not solve any particular real-world Troy and Miklos began working to extend the result with co-author problem, but its existence raises the possibility that a super-quadratic "It was Alexander Belov, who was spending two months at CQT. When quantum speed-up is possible for useful functions. like drop Alexander returned to Latvia, he brought in colleagues there. As soon everything, as the team spotted the implications for quantum query complexity, i The results appear in the preprint "Separations in Query Complexity work on this" "it was like drop everything, work on this," says Troy. "It was extremely Based on Pointer Functions" by Andris Ambainis, Kaspars Balodis, Troy Lee fast. The whole paper took maybe two weeks to write." Alexander Belov and Juris Smotrovs from the University of Latvia and Troy Lee and Miklos Santha from CQT. The work was also selected (i) Preprint at http://eccc.hpi-web.de/report/2015/098/ for a plenary talk at the 19th Conference on Quantum Information (ii) Preprint at http://arxiv.org/abs/1511.01937 Processing (QIP) held in Canada in January 2016 and will be (iii) Preprint at http://eccc.hpi-web.de/report/2015/050/ presented at the 48th Annual Symposium on the Theory of Computing (STOC) in the US in June 2016.
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Centre for Quantum Technologies I Annual Report 2015 35 , + Centre for Quantum Technologies I Annual Report 2015 I Technologies Centre for Quantum , 032108 (2015) , 053024 (2015) 92 17
co-authored with CQT colleagues Kyle Arnold, Elnur co-authored with CQT colleagues Kyle Arnold, ii ions. So far clocks using ions have used only one, because ions. So far clocks using + ions could work in a lattice because they have ‘negative ions could work in a lattice because they have Phys. Rev. A + New J. Phys. leads to greater stability. JILA’s record-holding Strontium clock uses clock Strontium record-holding JILA’s stability. greater to leads atoms neutral that is drawback Their atoms. of thousands of lattice a constantly be to have clocks the meaning trap, the escape easily Because cycle. measurement the in deadtime causes That up. topped micromotion the if atoms, neutral than trapped effectively more are ions all. of option best the offer could lattice ion an solved, be can problem Lu Prize winner David polarisability’. Researchers including Nobel this property leads to the Wineland observed as long ago as 1998 that shift caused by existence of a ‘magic frequency’ where the frequency caused by the field. the ions’ motion cancels the shift in energy levels In a paper collaborator Hajiyev, Eduardo Paez, Chern Hui Lee and international of this effect for Lu John Bollinger, Murray worked out the details the current state of concluding that “this approach could outperform and accuracy.” The the art by an order of magnitude in both stability Funding to pursue the group has been awarded A*STAR Public Sector project. (i) (ii) very long lifetime, of around 60 hours. This means it has a very narrow This means it has of around 60 hours. very long lifetime, based for a reference. “Clocks – just what you want frequency width limited will eventually become with a lifetime of seconds on transitions not happen for Lutetium,” says Murray. by the lifetime. This will Strength in numbers in the CQT group’s proposal, too. Murray and There’s another novelty they can build a clock with a crystal of around his collaborators think 100 Lu is used to trap ions cause micromotion that the radiofrequency fields collections. hard to control in larger the advantage of faster readout, which Having more atoms brings ions that has a + . Figure + Lu 176 make it a strong clock + transition. The scheme to the right shows the 1 D 3 -> 0 S The energy levels of Lu to the candidate when hyperfine averaging is applied 1 hyperfine splitting for this transition in hyperfine splitting adapted from ref (i). . This hyperfine averaging means you can consider atomic . This hyperfine averaging means you can consider < i angular momentum (J=0) which are intrinsically resistant to external angular momentum (J=0) which are intrinsically an effective J=0 fields. Murray realised that you can instead create multiple hyperfine level by averaging over a set of transitions between levels transitions that were previously ruled out. the criteria for Murray zoomed in on Lutetium because it fulfills a nuclear magnetic hyperfine averaging to work, that the atom have angular momentum. moment greater than the transition states’ orbital He had also spotted a promising clock transition in Lu that transition frequency as constant as possible, the atoms must be as possible, the atoms frequency as constant that transition electric fields such as magnetic and external influences protected from clocks have Previous atomic the atom’s energy levels. that can shift between energy levels with zero orbital been based on transitions and is so -18 Looking to Lutetium in Lutetium ions – Murray’s group wants to use an optical transition – to develop this next not previously considered a clock candidate on a novel idea he has generation of technology. The scheme relies dubbed ‘hyperfine averaging’. laser that define the In an atomic clock, it’s the oscillations of the is being a stable tick-tock for counting time. The role of the atoms frequency reference. The laser is tuned to match the energy gap of an atomic transition from a lower to a higher energy level. To keep is even defined in terms of a resonance frequency of Caesium atoms frequency of Caesium in terms of a resonance is even defined at 9,192,631,770Hz. at microwave frequency lags the state of But the Caesium standard clock based on neutral Strontium atoms the art. An optical atomic for being the world’s most accurate and currently holds the record at JILA, a joint institute of the University of stable clock. Located the US National Institute of Standards and Colorado Boulder and seconds with an accuracy of 10 Technology, it measures – gain nor lose a second in 15 billion years stable that it would neither about the age of the Universe. time. Einstein’s general Clocks this precise can detect gravity warping gravitational field. relativity predicts that clocks tick faster in a weaker the gravitational shift "Our performance means that we can measure the Earth's surface," when you raise the clock just 2 centimeters on of CQT’s Scientific JILA’s Jun Ye told media in 2015. Ye is a member Advisory Board. atomic clocks With just a little more improvement in performance, known as ‘relativistic could be used for mapping the Earth’s shape, modelling, monitoring geodesy’, with applications in Earth systems second could end up and mineral and oil exploration. Ultimately the being redefined, too. synchronizing internet traffic. By international agreement, the second agreement, internet traffic. By international synchronizing
Projects in focus in Projects (right) is pictured with group member Kyle Arnold. (right) is pictured with group member Kyle Arnold. This is the lab where the work will happen. Murray This is the lab where the work will happen. Murray <
build the world’s best atomic clock build the world’s Murray Barrett’s group at CQT aims to at CQT aims Barrett’s group Murray TIME KEEPERS TIME technology, from creating Global Positioning System signals to Atomic clocks are already behind a surprising amount of modern role in tomorrow’s technology,” Murray says. role in tomorrow’s technology,” Murray says. clock that could better today’s best time-keepers. It’s about more than clock that could better today’s best time-keepers. play a crucial pushing limits. “New generation clocks will inevitably Murray’s group has proposed a novel scheme for building an atomic Murray’s group has proposed a novel scheme want to be able to measure time in billionths of a billionth of a second. want to be able to measure time in billionths For most of us, knowing the time to within a few minutes is precise For most of us, knowing the time to within a few Murray Barrett enough. But physicists like CQT Principal Investigator 6 34 Projects in focus < Famous physicists from the past including Niels 6 Bohr and Albert Einstein appear as characters in the comic An educational perspective Kwek Leong Chuan There is a beautiful saying: “A picture paints a thousand words.” Educational research has consistently pointed to the effectiveness of combining text with images to improve retention and reading performances (see Educ. Psychol. 14, 5 (2002)). Otto’s book weaving the somewhat mysterious world of quantum physics into a MEET THE storyboard of comics can tap into this effect. The use of comics as an educational medium has been generally QUANTUM BUNNY underrated. For a time comics were even suspected of being bad influences, although proposals for using them in education can CQT Outreach Fellow Otto Fong creates be found as early as 1944. W. Sones, a Professor of Education science comics for kids at the University of Pittsburgh, wrote then (J Educ Sociol. 18, 232 (1944)), “It is appropriate to examine from the standpoint of When author Otto Fong applied for a writer’s residency at CQT, he the educational method this most recently arrived entertainment wrote “If getting quantum mechanics to the young masses is what device that has attracted such an extraordinary following.” CQT seeks, I'm your artist". With the launch in October 2015 of The Quantum Bunny comic book for kids from primary school up, he The sales of Otto's books and others show there is popular delivered on that promise. “The poppy visuals and adventure story will appeal appetite today for such educational comics. A manga guide to to kids, and might just serve as a stepping stone physics by my friend Professor Hideo Nitta, who is also currently Otto is the creator of the Sir Fong’s Adventures in Science series, of "This book will not teach quantum mechanics to young people, but it the Chair of the Commission C14 (Physics Education) of the The Quantum Bunny for them to learn more about the wonders of the which is book five. He came up with the idea will make some of the ideas familiar" he says. “It serves up a fun story quantum world.” International Union of Pure and Applied Physics, has been for the comics when he was a science teacher trying to enthuse his about a misunderstood bunny in his quest to be accepted.” translated into several languages. students. He’s now a full-time author and cartoonist. Sonny Liew The book was launched at the Singapore Writer’s Festival, earning a Comic artist, The Art of Charlie Chan Hock Chye Indeed, case studies by educators trying to establish and sustain Whereas the first Sir Fong books concentrated on teaching topics feature in Today newspaper and a spot on the ‘bestsellers’ shelf of the interest in science learning have found that comics help (see for from the science syllabus, The Quantum Bunny brings his readers festival bookshop. Cover blurbs came from US cartoonist Larry Gonick example CBE Life Sci. Educ. 10, 309 (2011)). I believe comics to the forefront of modern research. Otto spent six months as an and local artists Sonny Liew and Evangeline Neo, while CQT’s Director provide an extremely powerful and effective means of science Outreach Fellow at CQT, attending undergraduate lectures and Artur Ekert wrote the foreword communication. meeting one-on-one with CQT researchers. But the reviews that matter most will be from the audience the < CQT researchers Tan Kwek Leong Chuan is a Principal Investigator at CQT doing research in Reasoning that quantum physics would be hard for children just book is written for: Singapore’s school-age children. As Otto tours Peng Kian, Manas theoretical quantum information. He is also a lecturer at Singapore’s National learning mathematics to grasp, he has wrapped the science into Mukherjee and Loh Institute of Education and a former physics teacher. schools giving his talks on science, we look forward to gathering Huanqian have a well-known story. The book is a retelling of the Chinese fable of their feedback. The Quantum Bunny is available now from Singapore cameo roles the Monkey King causing uproar in heaven, now starring Qbit the bookshops with an e-book to follow. quantum rabbit. Otto swapped other characters in the classic tale for scientists. Check www.ottoniumcomics.com for news.
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Centre for Quantum Technologies I Annual Report 2015 7 Education 2015 GRADUATES Markus Philipp Baden Quantum Optics with Cavity-assisted Raman Transitions Supervised by Murray Barrett
Gurpreet Kaur Gulati Narrowband Photon Pairs from a Cold Atomic Vapour for SCIENTISTS Interfacing with a Single Atom <
< Supervised by Christian Kurtsiefer “I was a physics undergraduate “CQT offers lots of room for IN TRAINING at NUS and did a project at CQT. your own personal growth. I liked it so much I stayed! I’ve Besides my main project, my Hu Yu-Xin CQT welcomes students from all over the world to begin had great opportunities, like professor has encouraged me Artificial Gauge Fields and Topological Effects in Quantum Gases spending a semester in Canada to learn more about what I like research in the exciting field of quantum technologies taking different courses. ” and even try different projects Supervised by Berge Englert for a while.” PhD Programme Siddarth Koduru Joshi It is part of the Centre’s mission to offer high-quality education Entangled Photon Pairs: Efficient Generation and Detection, and for graduate students. Students joining CQT are immersed in the Goh Koon Tong Nguyen Chi Huan Bit Commitment CQT PhD student CQT PhD student fast moving field of quantum technologies, where research spans Valerio Scarani’s group Christian Kurtsiefer’s group Supervised by Christian Kurtsiefer experimental and theoretical physics and computer science. Attila Pereszlenyi In 2015, CQT had 69 students studying under its PhD@CQT Studies in Models of Quantum Proof Systems programme, which offers a generous scholarship plus allowances Supervised by Rahul Jain for travel and other expenses. Doctoral degrees are awarded by the National University of Singapore, consistently ranked among the Bharath Srivathsan leading universities in the world. CQT also accepts students funded Heralded Single Photons for Efficient Interaction with Single by other sources. Atoms Find more information on the student programme and a description Supervised by Christian Kurtsiefer of how to apply at quantumlah.org/openings/phd Tan Kok Chuan Bobby Quantum Correlations in Composite Particles < < < Internships < “I love physics but I did my "Being part of CQT as a PHD “I enjoy the atmosphere here. I "A good thing is that CQT Supervised by Dagomir Kaszlikowski CQT offers internships to students near the end of an undergraduate undergraduate degree in student has been so far one find it friendly and constructive. has many researchers who degree or during masters studies who are contemplating a career in computer science. Quantum of the best experiences in my The physics community in come from different places. research. Applications should be made directly to the PI with whom information is the perfect way life. I've had the opportunity Singapore may be small but it is Singapore is full of diversity. Yang Tzyh Haur to join them together. Having to meet a lot of new people very active in terms of hosting This experience is different for Device Independent Playground: Investigating and Opening Up the student would like to work. Successful interns making follow up that mix of people here keeps and learn the most modern conferences and inviting big me." applications to the PhD@CQT programme will be given high priority. your mind fresh.” techniques in quantum international speakers.” a Quantum Black Box. physics." Supervised by Valerio Scarani
Anurag Anshu Francesca Tosto Ulrike Bornheimer Yoshihito Hotta Find CQT PhD theses at quantumlah.org/publications/theses.php CQT PhD student CQT PhD student CQT PhD student CQT intern Rahul Jain’s group Rainer Dumke's group Berge Englert’s group Vlatko Vedral's group 38 39
Centre for Quantum Technologies I Annual Report 2015 7 Education
Ved Prakash Gurpreet Kaur Gulati Yang Tzyh Haur Data Scientist Postdoc Model Validation PUTTING A Ministry of Defence, Singapore University of Sussex, UK DBS Bank, Singapore What was your path to working at MINDEF? What research are you doing now? What do you do at DBS? My PhD with the CQT computer science group was on the I am working on a hybrid quantum system that links two vital I work in the model validation team. We make assessments of PHD TO USE design of streaming algorithims, both classical and quantum. fields of research: ion trap technologies and cavity quantum the mathematical models that the bank uses to perform risk Life after CQT The group has expertise in the mathematical study of how electrodynamics (CQED). I am part of the group of Professor management and reporting. My scope is mainly liquidity risk and algorithms work. I wanted to see how what I had learnt could be Mathias Keller at the University of Sussex. market risk. "We are proud of our PhD graduates for who they are as people, as applied in industry. well as the scientists they have become. Their training, skills and How is it different to doing your PhD? How did you end up working there? character mean they have a lot to contribute to society whatever they What is your role? I am more like a boss of PhDs now! But honestly, I am learning a choose to do next," says CQT Director Artur Ekert. I did an internship with DBS while I was still a student in CQT. I I am in the R&D team of the machine learning group. We try lot of new things and that’s really encouraging and motivating. wanted to look for an industry where I could use my skills and at to design algorithms that make predictions from large sets of the same time contribute to society. So what do our graduates do next? For 31 of the 34 CQT PhD students data. To work in R&D here, it is preferred that you have at least What’s your best memory of CQT? who have successfully defended their theses so far, their next job was a Masters degree. We are given an engineering problem and I made many good friends. CQT is like a family. People are What is your working day like? in academia. then have to explore methods to solve it. Like in research, this easily approachable and ready to help you, whether its admin Typically I come to the office and then start to think about what involves reading papers and building models. My experience staff, professors or the Centre's Director. projects are on hand and what analyses I want to do. It feels This year’s eight graduates have become postdocs at institutions at CQT helps me with the process of deciding how to attack a including CQT, the University of Waterloo in Canada, the Institute for very similar to what I did in CQT! The models are very much like problem. The discussions in group meetings also trained me in What do you hope to be doing 10 years from the models you would see in physics. Quantum Optics and Quantum Information in Austria and the Max how to present my work. now? Planck Institute for the Science of Light in Germany. Other graduates It’s a difficult question to answer, but one thing I’m sure of is that How do you benefit from your PhD training? have taken their skills into industry and government jobs. What is different to academic research? I like research and want to keep exploring this path. Some of the skills that you learn in PhD research are applicable In theoretical computer science, you analyse an algorithm to everywhere: you have to be critical and sharp, and you have to We've interviewed a few of our recent graduates about their know if it works, then you stop and publish it. Here you keep What else do you enjoy? experience after leaving CQT. Thank you Tzyh Haur, Gurpreet and get a good insight into a problem before you even start writing going, working with software developers to implement the Being from a small town in India, I always dreamt of travelling it down. Ved for telling us about your new roles. solution. I find that exciting. around the world. Thanks to my research career, through conferences and workshops, I've had the opportunity to visit What is the most useful thing you learned at CQT? Where do you see yourself in the future? places that I used to read about in books. I've also made good To look at things in an open-minded sense. I am definitely interested in staying in the field of machine connections through visiting different labs around the world. learning. In the future I may like to work on artificial intelligence.
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Centre for Quantum Technologies I Annual Report 2015 8 Listings PAPERS
Detection Loophole Attacks On Semi- Entanglement Sampling and Applications Optimal scaling of persistent currents for Quantum Game Players Can Have Quantum phase estimation using a multi- Tensor Networks And Graphical Calculus Optimality of entropic uncertainty Deploying quantum light sources on Device-Independent Quantum And Dupuis, Frederic; Fawzi, Omar; Wehner, interacting bosons on a ring Advantage Without Discord headed cat state For Open Quantum Systems relations nanosatellites I: lessons and perspectives Classical Protocols Stephanie Cominotti, M.; Rizzi, M.; Rossini, D.; Wei, Zhaohui; Zhang, Shengyu Lee, Su-Yong; Lee, Chang-Woo; Nha, Wood, Christopher J.; Biamonte, Jacob Abdelkhalek, Kais; Schwonnek, Rene; on the optical system Dall'Arno, Michele; Passaro, Elsa; IEEE Trans. Inf. Theory 61, 1093 (2015) Aghamalyan, D.; Amico, L.; Kwek, L. C.; TAMC 2015. 9076, 311 (2015) Hyunchul; Kaszlikowski, Dagomir D.; Cory, David G. Maassen, Hans; Furrer, Fabian; Duhme, Chandrasekara, R.; Tang, Z.; Tan, Y. Gallego, Rodrigo; Pawlowski, Marcin; Hekking, F.; Minguzzi, A. J. Opt. Soc. Am. 32, 1186 (2015) Quant. Inf. Comput. 15, 759 (2015) Joerg; Raynal, Philippe; Englert, Berthold- C.; Cheng, C.; Septriani, B.; Durak, K.; Acin, Antonio Lower Bounds On Information Complexity EPJ ST. 224, 519 (2015) The Third-Order Term in the Normal Georg; Werner, Reinhard F. Grieve, J. A.; Ling, A. Quantum Inf. Comput. 15, 0037 (2015) Via Zero-Communication Protocols And Approximation for the AWGN Channel Robust quantum metrological schemes Fooling-sets and rank Int. J. Quantum Inf. 13, 1550045 (2015) Proc. SPIE 9615, Quantum Applications Systematic evaluation of an atomic clock Tan, Vincent Yan Fu; Tomamichel, Marco based on protection of quantum Fisher Friesen, Mirjam; Hamed, Aya; Lee, Troy; Communications and Quantum Imaging Precise Evaluation of Leaked Information Kerenidis, Iordanis; Laplante, Sophie; at 2 x 10 (-18) total uncertainty IEEE Trans. Inf. Theory 61, 2430 (2015) information Theis, Dirk Oliver Spatially resolved ultrafast magnetic XIII, 96150S (2015) with Secure Randomness Extraction in Lerays, Virginie; Roland, Jeremie; Xiao, Nicholson, T. L.; Campbell, S. L.; Lu, Xiao-Ming; Yu, Sixia; Oh, C. H. European J. Combin. 48, 143 (2015) dynamics initiated at a complex oxide the Presence of Quantum Attacker David Hutson, R. B.; Marti, G. E.; Bloom, B. J.; There is Entanglement in the Nat. Commun. 6, 7282 (2015) heterointerface Single photon counting for space based Hayashi, Masahito SIAM J. Comput. 44, 1550 (2015) McNally, R. L.; Zhang, W.; Barrett, M. D.; Primes Second-Order Asymptotics for the Foerst, M.; Caviglia, A. D.; Scherwitzl, R.; quantum experiments Commun. Math. Phys. 333, 335 (2015) Safronova, M. S.; Strouse, G. F.; Tew, W. Latorre, Jose I.; Sierra, German Ground State Connectivity of Local Classical Capacity of Image-Additive Mankowsky, R.; Zubko, P.; Khanna, V.; Chandrasekara, R.; Tang, Z. K.; Tan, Y. No-signaling quantum key distribution: L.; Ye, J. Quantum Inf. Comput. 15, 622 (2015) Hamiltonians Quantum Channels Bromberger, H.; Wilkins, S. B.; Chuang, C.; Cheng, C.; Wildfeuer, C.; Ling, A. Teleparallel Gravity as a Higher Gauge solution by linear programming Gharibian, Sevag; Sikora, Jamie Tomamichel, Marco; Tan, Vincent Y. F. Nat. Commun. 6, 6896 (2015) Thermalization in a periodically Y. -D.; Lee, W. S.; Schlotter, W. F.; Proc. SPIE 9492, Advanced Photon Theory Hwang, Won-Young; Bae, Joonwoo; ICALP 9134, 617 (2015) Commun. Math. Phys. 338, 103 (2015) Turner, J. J.; Dakovski, G. L.; Minitti, M. Counting Techniques IX, 949209 (2015) Baez, John C.; Wise, Derek K. Killoran, Nathan An exact formulation of the time-ordered driven fully connected quantum Ising ferromagnet On Solving Systems of Diagonal Upper Bounds on Fourier Entropy P.; Robinson, J.; Clark, S. R.; Jaksch, D.; Commun. Math. Phys. 333, 153 (2015) QIP 14, 687 (2015) exponential using path-sums Triscone, J-M.; Hill, J. P.; Dhesi, S. S.; Error-Control Coding for Physical-Layer Giscard, P. -L.; Lui, K.; Thwaite, S. J.; Russomanno, Angelo; Fazio, Rosario; Polynomial Equations Over Finite Fields Chakraborty, Sourav; Kulkarni, Raghav; Secrecy Universal Subspaces for Local Unitary Quantropy Santoro, Giuseppe E. Ivanyos, Gabor; Santha, Miklos Lokam, Satyanarayana V.; S Cavalleri, A. Jaksch, D. Nat. Mater. 14, 883 (2015) Bloch, Matthieu; Hayashi, Masahito; Groups of Fermionic Systems Baez, John C.; Pollard, Blake S. J. Math. Phys. 56, 053503 (2015) EPL 110, 37005 (2015) FAW 2015 9130, 125 (2015) aurabh, Nitin Thangaraj, Andrew Chen, Lin; Chen, Jianxin; Dokovic, Entropy 17, 772 (2015) Computing & Combinatorics Towards witnessing quantum effects in Proc. IEEE 103, 1725 (2015) Dragomir Z.; Zeng, Bei On the Power of Parity Queries in Explicit relation between all lower bound Query Complexity in Expectation 9198, 771 (2015) Zitterbewegung in Bogoliubov's System techniques for quantum query complexity Kaniewski, Jedrzej; Lee, Troy; de Wolf, complex molecules Commun. Math. Phys. 333, 541 (2015) Boolean Decision Trees Farrow, T.; Taylor, R. A.; Vedral, V. Quantum Wiretap Channel With Li Yan; Su Hong-Yi; Zhang Fu-Lin; Chen Kulkarni, Raghav; Qiao, Youming; Sun, Magnin, Loick; Roland, Jeremie Ronald A Constructive Quantum Lovasz Local Non-Uniform Random Number and Its Radiation tolerance of opto-electronic Jing-Ling; Wu Chun-Feng; Int. J. Quantum Inf. 13, 1350059 (2015) ICALP 9134, 761 (2015) Lemma For Commuting Projectors Farad. Discuss. 184, 183 (2015) Xiaoming Exponent and Equivocation Rate of components proposed for space-based Kwek, Leong-Chuan TAMC 2015. 9076, 99 (2015) Sattath, Or; Arad, Itai Leaked Information quantum key distribution Commun. Theor. Phys. 63, 145 (2015) New Strong Direct Product Results in Reachability is in DynFO Quantum Inf. Comput. 15, 987 (2015) Controlling the interference of single Communication Complexity Datta, Samir; Kulkarni, Raghav; photons emitted by independent atomic Hayashi, Masahito Tan, Yue Chuan; Chandrasekara, Quantum and Randomized Query IEEE Trans. Inf. Theory 61, 5595 (2015) Rakhitha; Cheng, Cliff; Ling, Alexander Investigating properties of a family of Complexities Jain, Rahul Mukherjee, Anish; Schwentick, Thomas; sources J. Mod. Opt. 62, 1709 (2015) quantum Renyi divergences Santha, Miklos J. ACM 62, 20 (2015) Zeume, Thomas Cere, Alessandro; Leong, Victor; Kosen, State complexity and quantum Lin, Simon M.; Tomamichel, Marco TAMC 2015. 9076, 18 (2015) ICALP 9135, 159 (2015) Sandoko; Srivathsan, Bharath; Gulati, computation QIP 14, 1501 (2015) Gurpreet Kaur; Kurtsiefer, Christian Cai, Yu; Le, Huy Nguyen; Scarani, Valerio Proc. SPIE 9615, Quantum AdP. 527, 684 (2015) Communications and Quantum Imaging XIII, 96150Q (2015)
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Centre for Quantum Technologies I Annual Report 2015 8 Listings
Generalized Wong sequences and their Mimicking Dirac fields in curved Experimental realization of generalized Quantum macroscopicity versus Realization of a holonomic quantum Entanglement witness for spin glass Nondestructive selective probing of Correspondence between dark solitons applications to Edmonds' problems spacetime with fermions in lattices with qubit measurements based on quantum distillation of macroscopic computer in a chain of three-level Koh, C. Y.; Kwek, L. C. phononic excitations in a cold Bose gas and the type II excitations of the Lieb- Ivanyos, Gabor; Karpinski, Marek; Qiao, non-unitary tunneling amplitudes walks superpositions systems Physica A 420, 324 (2015) using impurities Liniger model Youming; Santha, Miklos Minar, Jiri; Gremaud, Benoit Zhao, Yuan-yuan; Yu, Neng-kun; Yadin, Benjamin; Vedral, Vlatko Gurkan, Zeynep Nilhan; Sjoqvist, Erik Hangleiter, D.; Mitchison, M. T.; Johnson, Karpiuk, Tomasz; Sowinski, Tomasz; J. Comput. Syst. Sci. 81, 1373 (2015) J. Phys. A 48, 165001 (2015) Kurzynski, Pawel; Xiang, Guo-yong; Li, Phys. Rev. A 92, 022356 (2015) Phys. Rev. Lett. 379, 3050 (2015) Physical characterization of quantum T. H.; Bruderer, M.; Plenio, M. B.; Gajda, Mariusz; Rzazewski, Kazimierz; Chuan-Feng; Guo, Guang-Can devices from nonlocal correlations Jaksch, D. Brewczyk, Miroslaw Monte Carlo sampling from the quantum Coherent quantum transport in disordered Phys. Rev. A 91, 042101 (2015) Space-Qualified Nanosatellite Thermalization of matter waves in Bancal, Jean-Daniel; Navascues, Miguel; Phys. Rev. A 91, 013611 (2015) Phys. Rev. A 91, 013621 (2015) state space. I systems: A unified polaron treatment of Electronics Platform for Photon Pair speckle potentials Scarani, Valerio; Vertesi, Tamas; Yang, Shang, Jiangwei; Seah, Yi-Lin; Ng, hopping and band-like transport Competing exotic quantum phases of Experiments Cherroret, Nicolas; Karpiuk, Tomasz; Tzyh Haur Challenging preconceptions about Bell Information-theoretic Bell inequalities Hui Khoon; Nott, David John; Englert, Lee, Chee Kong; Moix, Jeremy; Cao, spin-1/2 ultracold lattice bosons with Cheng, Cliff; Chandrasekara, Rakhitha; Gremaud, Benoit; Miniatura, Christian Phys. Rev. A 91, 022115 (2015) tests with photon pairs based on Tsallis entropy Berthold-Georg Jianshu extended spin interactions Tan, Yue Chuan; Ling, Alexander Phys. Rev. A 92, 063614 (2015) Vivoli, V. Caprara; Sekatski, P.; Bancal, Wajs, Marek; KurzyNski, Pawel; New. J. Phys. 17, 043017 (2015) J. Chem. Phys. 142, 164103(2015) Chang, Chia-Chen; Rousseau, Valery G.; J. Lightw. Technol. 33, 4799 (2015) Photonic lattice simulation of dissipation- J. -D.; Lim, C. C. W.; Christensen, B. G.; Kaszlikowski, Dagomir Scalettar, Richard T.; Batrouni, George G. Comparing different approaches for induced correlations in bosonic systems Martin, A.; Thew, R. T.; Zbinden, H.; Gisin, Phys. Rev. A 91, 012114 (2015) Monte Carlo sampling from the quantum Coherent superposition of current flows Phys. Rev. B 92, 054506 (2015) Few-photon transport in many-body generating random numbers device- Rai, Amit; Lee, Changhyoup; Noh, N.; Sangouard, N. state space. II in an atomtronic quantum interference photonic systems: A scattering approach independently using a photon pair source Changsuk; Angelakis, Dimitris G. Phys. Rev. A 91, 012107 (2015) State-dependent approach to entropic Seah, Yi-Lin; Shang, Jiangwei; Ng, device Limits to catalysis in quantum Lee, Changhyoup; Noh, Changsuk; Vivoli, V. Caprara; Sekatski, P.; Bancal, Sci. Rep. 5, 8438 (2015) measurement-disturbance relations Hui Khoon; Nott, David John; Englert, Aghamalyan, Davit; Cominotti, Marco; thermodynamics Schetakis, Nikolaos; Angelakis, Dimitris G. J-D; Lim, C. C. W.; Martin, A.; Thew, R. T.; Dissipation enhanced vibrational sensing Coles, Patrick J.; Furter, Fabian Berthold-Georg Rizzi, Matteo; Rossini, Davide; Hekking, Ng, N. H.; Mancinska, L.; Cirstoiu, C.; Phys. Rev. A 92, 063817 (2015) Zbinden, H.; Gisin, N.; Sangouard, N. Quantum dynamics in a tiered non- in an olfactory molecular switch Phys. Lett. A 379, 105 (2015) New. J. Phys. 17, 043018 (2015) Frank; Minguzzi, Anna; Kwek, Leong- Eisert, J.; Wehner, S. New. J. Phys. 17, 023023 (2015) Markovian environment Checinska, Agata; Pollock, Felix A.; Chuan; Amico, Luigi New. J. Phys. 17, 085004 (2015) Lensing effect of electromagnetically Fruchtman, Amir; Lovett, Brendon W.; Heaney, Libby; Nazir, Ahsan 'Momentum rejuvenation' underlies the Precision measurement of branching induced transparency involving a Creation of quantum error correcting Benjamin, Simon C.; Gauger, Erik M. J. Chem. Phys. 142, 025102 (2015) phenomenon of noise-assisted quantum fractions of Ba-138(+): Testing many- New. J. Phys. 17, 045023(2015) Optimal GHZ Paradox for Three Qubits Rydberg state codes in the ultrastrong coupling New. J. Phys. 17, 023063 (2015) energy flow body theories below the 1% level Ren, Changliang; Su, Hong-Yi; Xu, Zhen- Han, Jingshan; Vogt, Thibault; Manjappa, regime Hardy's paradox and measurement- Li, Ying; Caruso, Filippo; Gauger, Erik; De Munshi, D.; Dutta, T.; Rebhi, R.; Bridging the gap between the Jaynes- Peng; Wu, Chunfeng; Chen, Jing-Ling Manukumara; Guo, Ruixiang; Kiffner, Kyaw, T. H.; Herrera-Marti, D. A.; Solano, Superradiant decay and dipole-dipole disturbance relations Benjamin, Simon C. Mukherjee, M. Cummings and Rabi models using an Sci. Rep. 5, 013080(2015) Martin; Li, Wenhui E.; Romero, G.; Kwek, L. -C. interaction of distant atoms in a two-way Fujikawa, Kazuo; Oh, C. H.; Yu, Sixia New. J. Phys. 17, 013057 (2015) Phys. Rev. A 91, 040501 (2015) intermediate rotating wave approximation Phys. Rev. A 92, 063824 (2015) Phys. Rev. B 91, 064503 (2015) cascaded cavity QED system Phys. Rev. A 91, 012105 (2015) Wang, Yimin; Haw, Jing Yan Tuning energy transport using interacting Zeeb, Steffen; Noh, Changsuk; Parkins, Lamb shift of energy levels in quantum Coexistence of energy diffusion and local Phys. Lett. A 379, 779 (2015) vibrational modes Quantum correlations which imply Classification of macroscopic quantum A. S.; Carmichael, H. J. Topological basis associated with B-M-W rings thermalization in nonequilibrium XXZ spin Guo, Chu; Mukherjee, Manas; Poletti, causation effects Phys. Rev. A 91, 023829 (2015) algebra: Two-spin-1/2 realization Kryuchkyan, G. Yu; Kyriienko, O.; chains with integrability breaking Dario Fitzsimons, Joseph F.; Jones, Jonathan Farrow, Tristan; Vedral, Vlatko Wang, Gangcheng; Sun, Chunfang; Liu, Shelykh, I. A. Mendoza-Arenas, J. J.; Clark, S. R.; Phys. Rev. A 92, 023637 (2015) A.; Vedral, Vlatko Opt. Commun. 337, 22 (2015) Quantum state discrimination and its Bo; Liu, Ying; Zhang, Yan; Xue, Kang J. Phys. B 48, 025401 (2015) Jaksch, D. Sci. Rep. 5, 18281 (2015) applications Phys. Lett. A 379, 1 (2015) Phys. Rev. E 91, 042129 (2015) Bae, Joonwoo; Kwek, Leong-Chuan J. Phys. A 48, 083001 (2015)
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Centre for Quantum Technologies I Annual Report 2015 8 Listings
Evidence for the conjecture that sampling Any monotone property of 3-uniform A measure of majorization emerging from Semiclassical spectral function for matter Demonstrating quantum contextuality of The second laws of quantum Rydberg-Resolved Resonant Inelastic Maximization of Extractable Randomness generalized cat states with linear optics is hypergraphs is weakly evasive single-shot statistical mechanics waves in random potentials indistinguishable particles by a single thermodynamics Soft X-Ray Scattering: Dynamics at Core in a Quantum Random-Number hard Kulkarni, Raghav; Qiao, Youming; Sun, Egloff, D.; Dahlsten, O. C. O.; Renner, R.; Trappe, M. I.; Delande, D.; Mueller, C. A. family of noncontextuality inequalities Brandao, Fernando; Horodecki, Michal; Ionization Thresholds Generator Rohde, Peter P.; Motes, Keith R.; Knott, Xiaoming Vedral, V. J. Phys. A 48, 245102 (2015) Su, Hong-Yi; Chen, Jing-Ling; Liang, Ng, Nelly; Oppenheim, Jonathan; Rubensson, J. -E.; Soderstrom, J.; Haw, J. Y.; Assad, S. M.; Lance, A. M.; Paul A.; Fitzsimons, Joseph; Munro, Theoretical Computer Science New. J. Phys. 17, 073001 (2015) Yeong-Cherng Wehner, Stephanie Binggeli, C.; Grasjo, J.; Andersson, Ng, N. H. Y.; Sharma, V.; Lam, P. K.; William J.; Dowling, Jonathan P. 588, 16 (2015) Efficiency of quantum controlled non- Sci. Rep. 5, 11637 (2015) Proc. Natl Acad. Sci. U.S.A. 112, J.; Sathe, C.; Hennies, F.; Bisogni, Symul, T. Phys. Rev. A 91, 012342 (2015) Quantacell: powerful charging of quantum Markovian thermalization 3275 (2015) V.; Huang, Y.; Olalde, P.; Schmitt, T.; Phys. Rev. Applied 3, 054004 (2015) Practical Relativistic Bit batteries Mukherjee, V.; Giovannetti, V.; Fazio, R.; Quantum Discord for d circle times 2 Strocov, V. N.; Fohlisch, A.; Kennedy, B.; Information-theoretic Bell inequalities Commitment Binder, Felix C.; Vinjanampathy, Sai; Huelga, S. F.; Calarco, T.; Montangero, Systems Scalable quantum memory in the Pietzsch, A. Family of Bell-like Inequalities as Device- based on Tsallis entropy (vol 91, 012114, Lunghi, T.; Kaniewski, J.; Bussieres, F.; Modi, Kavan; Goold, John S. Ma, Zhihao; Chen, Zhihua; Fanchini, ultrastrong coupling regime Phys. Rev. Lett. 114, 133001 (2015) Independent Witnesses for Entanglement 2015) Houlmann, R.; Tomamichel, M.; Wehner, New. J. Phys. 17, 075015 (2015) New. J. Phys. 17, 063031 (2015) Felipe Fernandes; Fei, Shao-Ming Kyaw, T. H.; Felicetti, S.; Romero, G.; Depth Wajs, Marek; Kurzynski, Pawel; S.; Zbinden, H. Sci. Rep. 5, 10262 (2015) Solano, E.; Kwek, L. C. Capturing Exponential Variance Using Liang, Yeong-Cherng; Rosset, Denis; Kaszlikowski, Dagomir Phys. Rev. Lett. 115, 030502 (2015) Hierarchy of bounds on accessible Hong-Ou-Mandel interference between Sci. Rep. 5, 8621 (2015) Polynomial Resources: Applying Tensor Bancal, Jean-Daniel; Puetz, Gilles; Phys. Rev. A 91, 019903 (2015) information and informational power triggered and heralded single photons Iterated Gate Teleportation and Blind Networks to Nonequilibrium Stochastic Barnea, Tomer Jack; Gisin, Nicolas Speckle-intensity correlations of photons Dall'Arno, Michele from separate atomic systems Quantum Computation Negative refraction for incoherent atomic Processes Phys. Rev. Lett. 114, 190401 (2015) Mutual information as an order parameter scattered by cold atoms Phys. Rev. A 92, 012328 (2015) Leong, Victor; Kosen, Sandoko; Perez-Delgado, Carlos A.; Fitzsimons, matter waves Johnson, T. H.; Elliott, T. J.; Clark, S. R.; for quantum synchronization Mueller, Cord A.; Gremaud, Benoit; Srivathsan, Bharath; Gulati, Gurpreet Joseph F. Vogt, Thibault; Li, Wenhui Quantum Algorithm for Universal Quantum contextuality of a qutrit state Jaksch, D. Ameri, V.; Eghbali-Arani, M.; Mari, A.; Miniatura, Christian Kaur; Cere, Alessandro; Kurtsiefer, Phys. Rev. Lett. 114, 220502 (2015) Phys. Rev. A 91, 033634 (2015) Phys. Rev. Lett. 114, 090602 (2015) Implementation of the Projective Farace, A.; Kheirandish, F.; Giovannetti, Phys. Rev. A 92, 013819 (2015) Xu, Zhen-Peng; Su, Hong-Yi; Christian Measurement of Energy V.; Fazio, R. Chen, Jing-Ling Phys. Rev. A 91, 063829 (2015) Socioecological regime shifts in the Proposed Parametric Cooling of Bilayer Revealing Genuine Optical-Path Nakayama, Shojun; Soeda, Akihito; Phys. Rev. A 91, 012301 (2015) Communication Tasks with Infinite Phys. Rev. A 92, 012104 (2015) setting of complex social interactions Cuprate Superconductors by Terahertz Entanglement Murao, Mio Quantum-Classical Separation Beyond Gisin's Theorem and its Sugiarto, Hendrik Santoso; Chung, N Excitation Majorana transport in superconducting Monteiro, F.; Vivoli, V. Caprara; Guerreiro, Phys. Rev. Lett. 114, 190501 (2015) Detecting two-site spin-entanglement in Perry, Christopher; Jain, Rahul; Applications: Violation of Local Realism ing Ning; Lai, Choy Heng; Denny, S. J.; Clark, S. R.; Laplace, Y.; T.; Martin, A.; Bancal, J. -D.; Zbinden, H.; many-body systems with local particle- Oppenheim, Jonathan nanowire with Rashba and Dresselhaus by Two-Party Einstein-Podolsky-Rosen Chew, Lock Yue Cavalleri, A.; Jaksch, D. Developing a field independent frequency spin-orbit couplings Thew, R. T.; Sangouard, N. number fluctuations Phys. Rev. Lett. 115, 030504 (2015) Steering Phys. Rev. E 91, 062804 (2015) Phys. Rev. Lett. 114, 137001 (2015) Phys. Rev. Lett. 114, 170504 (2015) reference Mazza, Leonardo; Rossini, Davide; Fazio, You, Jia-Bin; Shao, Xiao-Qiang; Tong, Chen, Jing-Ling; Su, Hong-Yi; Xu, Zhen- Barrett, M. D. Rosario; Endres, Manuel Quantum plasmonic excitation Qing-Jun; Chan, A. H.; Oh, C. H.; Vedral, Peng; Wu, Yu-Chun; Wu, Chunfeng; Ye, Quantum thermodynamics of general Shortcut to Adiabaticity in the Lipkin- New. J. Phys. 17, 053024 (2015) New. J. Phys. 17, 013015 (2015) in graphene and loss-insensitive Vlatko Xiang-Jun; Zukowski, Marek; Kwek, L. C. quantum processes Meshkov-Glick Model propagation J. Phys. Condens. Matter Sci. Rep. 5, 11624 (2015) Binder, Felix; Vinjanampathy, Sai; Modi, Campbell, Steve; De Chiara, Gabriele; Local discrimination of four or more Hanson, George W.; Gangaraj, S. A. 27, 225302 (2015) Kavan; Goold, John Paternostro, Mauro; Palma, G. Massimo; maximally entangled states Hassani; Lee, Changhyoup; Angelakis, Phys. Rev. E 91, 032119 (2015) Fazio, Rosario Tian, Guojing; Yu, Sixia; Gao, Fei; Wen, Dimitris G.; Tame, Mark Phys. Rev. Lett. 114, 177206 (2015) Qiaoyan; Oh, C. H. Phys. Rev. A 92, 013828 (2015) Phys. Rev. A 91, 052314 (2015)
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Centre for Quantum Technologies I Annual Report 2015 8 Listings
Optical simulation of charge conservation Entropy bounds for quantum processes Least-bias state estimation with Simulation and detection of photonic Approaching Tsirelson's Bound in a A miniaturised, nested-cylindrical Fluctuation properties of laser light Polarization entanglement and quantum violation and Majorana dynamics with initial correlations incomplete unbiased measurements Chern insulators in a one-dimensional Photon Pair Experiment electrostatic analyser geometry for after interaction with an atomic system: beats of photon pairs from four-wave Keil, Robert; Noh, Changsuk; Rai, Amit; Vinjanampathy, Sai; Modi, Kavan Rehacek, Jaroslav; Hradil, Zdenek; Teo, circuit-QED lattice Poh, Hou Shun; Joshi, Siddarth K.; Cere, dual electron and ion, multi-energy Comparison between two-level and mixing in a cold Rb-87 ensemble Stuetzer, Simon; Nolte, Stefan; Angelakis, Phys. Rev. A 92, 052310 (2015) Yong Siah; Sanchez-Soto, Luis L.; Ng, Hui Mei, Feng; You, Jia-Bin; Nie, Wei; Fazio, Alessandro; Cabello, Adan; measurements multilevel atomic transitions G.K. Gulati, B. Srivathsan, B. Chng, A. Dimitris G.; Szameit, Alexander Khoon; Chai, Jing Hao; Englert, Berthold- Rosario; Zhu, Shi-Liang; Kwek, L. C. Kurtsiefer, Christian Bedington, Robert; Kataria, Dhiren; Lezama, A.; Rebhi, R.; Kastberg, A.; Cere, C. Kurtsiefer Optica 2, 454 (2015) Coherent Backscattering Reveals the Georg Phys. Rev. A 92, 041805 (2015) Phys. Rev. Lett. 115, 180408 (2015) Smith, Alan Tanzilli, S.; Kaiser, R. New J. Phys. 17, 093034 (2015) Anderson Transition Phys. Rev. A 92, 052303 (2015) Nucl. Instr. Meth. Phys. Res. Phys. Rev. A 92, 033853 (2015) Entropic Tests of Multipartite Nonlocality Ghosh, S.; Delande, D.; Miniatura, C.; Local discrimination of qudit lattice states Berry curvature of interacting bosons in a 793, 92 (2015) Fast non-Abelian geometric gates via and State-Independent Contextuality Cherroret, N. Quantum entanglement from random via commutativity honeycomb lattice Prospects for atomic clocks based on transitionless quantum driving Raeisi, Sadegh; Kurzynski, Pawel; Phys. Rev. Lett. 115, 200602 (2015) measurements Tian, Guojing; Yu, Sixia; Gao, Fei; Wen, Li, Yun; Sengupta, Pinaki; Batrouni, Gaussian private quantum channel with large ion crystals J. Zhang, Thi Ha Kyaw, D. M. Tong, E. Kaszlikowski, Dagomir Minh Cong Tran; Dakic, Borivoje; Arnault, Qiaoyan; Oh, C. H. George G.; Miniatura, Christian; squeezed coherent states Arnold, Kyle; Hajiyev, Elnur; Paez, Sjoqvist, L.C. Kwek Phys. Rev. Lett. 114, 200401 (2015) Realization of adiabatic Aharonov-Bohm Francois; Laskowski, Wieslaw; Paterek, Phys. Rev. A 92, 042320 (2015) Gremaud, Benoit Jeong, Kabgyun; Kim, Jaewan; Eduardo; Lee, Chern Hui; Barrett, M. D.; Sci. Rep. 5, 18414 (2015) scattering with neutrons Tomasz Phys. Rev. A 92, 043605 (2015) Lee, Su-Yong Bollinger, John Floquet control of quantum dissipation in Sjoqvist, Erik; Almquist, Martin; Mattsson, Phys. Rev. A 92, 050301 (2015) Cavity enhanced atomic magnetometry Sci. Rep. 5, 13974 (2015) Phys. Rev. A 92, 032108 (2015) Nonlocality and conflicting interest spin chains Ken; Gurkan, Zeynep Nilhan; Hessmo, Crepaz, Herbert; Ley, Li Yuan; Density fluctuations in a quasi-one- games Chen, Chong; An, Jun-Hong; Luo, Hong- Bjorn Quantum information approach to Bose- Dumke, Rainer dimensional Bose gas as observed in Half-skyrmion and vortex-antivortex pairs Equality, Revisited Anna Pappa, Niraj Kumar, Thomas Gang; Sun, C. P.; Oh, C. H. Phys. Rev. A 92, 052108 (2015) Einstein condensation of composite Sci. Rep. 5, 15448 (2015) free expansion in spinor condensates R. C. Bottesch, D. Gavinsky, H. Klauck Lawson, M. Santha, S. Zhang, Eleni Phys. Rev. A. 91 052122 (2015) bosons Gawryluk, Krzysztof; Gajda, Mariusz; Hu, Yu-Xin; Miniatura, Christian; International Symposium MFCS Diamanti, I. Kerenidis Cooperative Emission of a Pulse Train in Lee, Su-Yong; Thompson, Jayne; Raeisi, Dynamics of quantum correlation Brewczyk, Miroslaw Gremaud, Benoit 2, 127 (2015) Phys. Rev. Lett. 020401 (2015) Imaging single Rydberg electrons in a an Optically Thick Scattering Medium Sadegh; Kurzynski, Pawel; Kaszlikowski, between separated nitrogen-vacancy Phys. Rev. A 92, 043607 (2015) Phys. Rev. A 92, 033615 (2015) Bose-Einstein condensate Kwong, C. C.; Yang, T.; Delande, D.; Dagomir centers embedded in plasmonic Correlation in Hard Distributions in Distributed Computation of Large-scale Karpiuk, Tomasz; Brewczyk, Miroslaw; Pierrat, R.; Wilkowski, D. New. J. Phys. 17, 113015 (2015) waveguide A high flux source of cold Nonclassicality of Temporal Correlations Communication Complexity Graph Problems Rzazewski, Kazimierz; Gaj, Anita; Phys. Rev. Lett. 115, 223601 (2015) Yang, Wan-li; An, Jun-Hong; Zhang, strontium atoms Brierley, Stephen; Kosowski, Adrian; R. C. Bottesch, D. Gavinsky, H. Klauck H. Klauck, Danupon Nanongkai, Gopal Balewski, Jonathan B.; Krupp, Alexander Quantum walk as a simulator of nonlinear Cheng-jie; Chen, Chang-yong; Oh, C. H. Yang, Tao; Pandey, Kanhaiya; Pramod, Markiewicz, Marcin; Paterek, Tomasz; RANDOM 544 (2015) Pandurangan, Peter Robinson T.; Schlagmueller, Michael; Loew, Robert; Verifiable Measurement-Only Blind dynamics: Nonlinear Dirac equation and Sci. Rep. 5, 15513 (2015) Mysore Srinivas; Leroux, Frederic; Przysiezna, Anna ACM SIAM SODA 391 (2015) Quantum Computing with Stabilizer Hofferberth, Sebastian; Pfau, Tilman solitons Kwong, Chang Chi; Hajiyev, Elnur; Chia, Phys. Rev. Lett. 115, 120404 (2015) Pulse-splitting in light propagation New. J. Phys. 17, 053046 (2015) Testing Lee, Chang-Woo; Kurzynski, Pawel; Nha, THz-Frequency Modulation of the Zhong Yi; Fang, Bess; Wilkowski, David Hayashi, Masahito; Morimae, Tomoyuki Hubbard U in an Organic Mott Insulator State-independent contextuality sets through N-type atomic media due to an Hyunchul Eur. Phys. J. D 69, 226 (2015) interplay of Kerr-nonlinearity and group Genuine Multipartite Entanglement Phys. Rev. Lett. 115, 220502 (2015) Phys. Rev. A 92, 052336 (2015) Singla, R.; Cotugno, G.; Kaiser, S.; Foerst, for a qutrit M.; Mitrano, M.; Liu, H. Y.; Cartella, A.; Triangular and honeycomb lattices of cold Xu, Zhen-Peng; Chen, Jing-Ling; velocity dispersion without Multipartite Correlations Coherence-assisted single-shot cooling Rajitha K. V., Tarak N. Dey, Joerg Evers, Schwemmer, Christian; Knips, Lukas; Asymptotic compatibility between local- Manzoni, C.; Okamoto, H.; Hasegawa, T.; atoms in optical cavities Su, Hong-Yi by quantum absorption refrigerators operations-and-classical-communication Clark, S. R.; Jaksch, D.; Cavalleri, A. Safaei, Shabnam; Miniatura, Christian; Phys. Lett. A 379, 1869(2015) Martin Kiffner Minh Cong Tran; de Rosier, Anna; Mitchison, Mark T.; Woods, Mischa P.; Phys. Rev. A 92, 023840 (2015) Laskowski, Wieslaw; Paterek, Tomasz; conversion and recovery Phys. Rev. Lett. 115, 187401 (2015) Gremaud, Benoit Prior, Javier; Huber, Marcus Ito, Kosuke; Kumagai, Wataru; Phys. Rev. A 92, 043810 (2015) Simulating Bosonic Baths with Error Bars Weinfurter, Harald New. J. Phys. 17, 115013 (2015) Woods, M. P.; Cramer, M.; Plenio, M. B. Phys. Rev. Lett. 114, 180501 (2015) Hayashi, Masahito Phys. Rev. A 92, 052308 (2015) Phys. Rev. Lett. 115, 130401 (2015)
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Centre for Quantum Technologies I Annual Report 2015 8 Listings
EVENTS
Conferences & Workshops
Date Event Venue 7 Dec 2015 CQT Annual Symposium: The Famous, The Bit & The University Hall, NUS Quantum
28 Jun – 3 Jul 2015 The 22nd International Conference on Laser Shangri-La's Rasa Sentosa Resort & Spectroscopy, ICOLS 2015 Spa
26–27 Mar 2015 UK-Singapore Quantum Symposium University Hall, NUS
19–20 Jan 2015 UMI Majulab Kick-Off Meeting University Hall, NUS
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Centre for Quantum Technologies I Annual Report 2015 Public outreach Listings In the news 8 CQT or CQT research was mentioned in over 40 news stories in 2015. CQT participated in three public exhibitions this Highlights include: year, including collaborating with the NUS Science Demo Lab to run a one day quantum showcase at • PI Valerio Scarani recorded a segment on quantum randomness the ArtScience Museum. for The Academic Minute, a public radio show aired in the US and available online. We co-organized three public talks with the Science OUTREACH • Singapore’s Straits Times newspaper reported the recovery of a Centre Singapore in 2015, two in conjunction with CQT satellite payload that had been presumed lost after the rocket conferences hosted by CQT. CQT online launching it exploded. The centre’s website at quantumlah.org • Singapore’s HerWorld CQT’s Director Artur Ekert was in a panel offers up to date news, event listings and magazine profiled PI Kwek discussion at the World Science Festival in New links to the group’s research pages. It Leong Chuan (pictured) in a York in May. He also spoke to an audience received over 70,000 visitors in 2015. feature about men fighting including the public, policymakers and media at the for women's rights, noting Annual Meeting of the American Association for the CQT’s YouTube channel hosts videos his work supporting women Advancement of Science in San Jose in February. including interviews, artistic shorts and in physics. recorded colloquiua, accumulating over • The online news portal 700 hours of ‘watch time’ in 2015. Phys.Org carried seven stories in 2015 about Special projects CQT is also active on Facebook (2.2k research involving CQT The Quantum Shorts contest series reached more than 10,000 people followers) and Twitter (1.5k followers). < scientists. Photo Credit: © 2015 SPH Magazines online in 2015. After CQT awarded prizes for 2014’s short film contest Pte Ltd. Reproduced with permission. (see p. 22), our new competition for quantum-inspired flash fiction drew over 400 entries. The 2015 contest is supported by media partners Schools outreach Scientific American, Nature and Tor and international scientific partners Some 180 young students visited CQT this year. These visits the Australian Research Council Centre of Excellence for Engineered ranged from lab tours to week-long shadowing experiences Quantum Systems, the Institute for Quantum Computing at the University and a three-day workshop on quantum physics and of Waterloo, the Institute for Quantum Information at Caltech and the Joint cryptography organized by the Centre’s postdocs. Quantum Institute of the University of Maryland and National Institute of Standards and Technology. Outreach Fellow Otto Fong created Sir Fong’s Adventures in Science Book 5: The We welcomed Tania De Rozario Quantum Bunny to (pictured) as CQT writer-in- introduce quantum residence for five months from physics to the under September. She is writing a novella 16s (see pp 36–37). that borrows from quantum physics to inform both its narrative and its PI Kwek Leong Chuan structure, in a choose-your-own- offered a workshop adventure style of story. Tania's at the Thai Science appointment follows the conclusion Camp in Bangkok. of playwright Eleanor Wong’s 2014 residency (see p. 20). 52 53
Centre for Quantum Technologies I Annual Report 2015 8 Listings
Scott Aaronson Ignacio Cirac Hans Kuiper Liu Peiliang MIT, US Max-Planck-Institute for Quantum Optics, TU Delft, the Netherlands National Institute of Information and Germany Communications Technology, Japan Charles Adam Alex Kuzmich Durham University, UK Samir Datta University of Michigan, US Tilman Pfau Chennai Mathematical Institute, India Universität Stuttgart, Germany Luigi Amico Jesper Larsen Uni-Catania, Italy Ronald de Wold GOM-Space, Denmark Blake Pollard CWI, Amsterdam, The Netherlands University of California Riverside, US Rotem Arnon Friedman Su-Yong Lee ETH, Switzerland Michel de Rougemont Korea Institute for Advanced Study Chabely Pollier Université Paris VII, France TU Delft, the Netherlands Bai Xueliang Dai Li University of Sydney, Austria Dainis Dravins National Chung Hsing University, Taiwan Youming Qiao Lund Observatory, Sweden Centre for Quantum Computation and Nikhil Balaji Chai Lingyun Intelligent Systems, University of Technology Chennai Mathematical Institute, India Feng Xunli Fudan University, China Sydney, Australia Shanghai Normal University, China Alexander Belov Nana Liu Apichayaporn Ratkata MIT, US Brendan Fong University of Oxford, UK Chiang Mai University, Thailand University of Oxford, UK VISITORS Benoit Descamps Liu Jinming Rakesh Roshan Vienna Center for Quantum Science and Andrew Garner East China Normal University Isis Innovation Ltd, UK Technology, Austria University of Oxford, UK Frederic Magniez Christophe Salomon Nicholas Bigelow Yuval Gefen CNRS, France CNRS, France University of Rochester, US Weizmann Institute of Science, Israel Cyril Stark Stanley Williams Serge Massar Luis Sanchez Soto MIT, US Hewlett Packard Labs, US Alessandro Bisio John Goold Université Libre de Bruxelles, Belgium Universidad Complutense de Madrid, Spain Pavia University, Italy International Centre for Theoretical Physics, Daniel Sternheimer Bai Xueliang Trieste, Italy Max Frenzel Adam Sawicki Rikkyo University, Japan & Université de The University Of Sydney, Australia Blair Blakie Imperial College, UK MIT, US Bourgogne, France University of Otago, New Zealand Kosuke Ito Yang WanLi Nagoya University, Japan Gerard Milburn Frank Scheffold Jun Suzuki Chinese Academy of Science Adam Bouland University of Queensland, Australia University of Fribourg, Switzerland The University of Electro-Communications, MIT, US Michael Joyce Japan Jun Ye Université Pierre et Marie Curie - Paris VI, Michele Mosca Daniel Schlenk NIST, Boulder, US Philippe Bouyer IQC, University of Waterloo, Canada Nickos Sxetakis France Ludwig-Maximilians-Universität München, Ki-Hyuk Yee Laboratoire Charles Fabry, France Germany Technical University of Crete, Greece Richard Jozsa Cord Muller Hanyang University, South Korea Michael Brooks University of Cambridge, UK University of Konstanz, Germany Jörg Schmiedmayer Anna Szymusiak Freelance writer, UK Institute of Mathematics, Krakow, Poland Zhen Yizheng, Tayebeh Naseri Vienna Center for Quantum Science and University of Science and Technology of An Jun-Hong Technology, Austria Chen Qing Lanzhou University, China Sharif University of Technology, Iran Marco Tomamichel China Yun Nan University, China University of Sydney, Australia Stefan Nimmrichter Ulrich Schollwöck Dahyun Yum EuGene Kim LMU, Germany Kai Chen University of Sydney, Australia University of Duisburg-Essen, Germany Alessandro Tosini Tsinghua University, China University of Science and Technology of China Pavia University, Italy Lukasz Pawela Robert Sewell Yicong Zheng Robin Kothari ICFO - Institut de Ciències Fotòniques, Spain Zhang Chengjie MIT, US Institute of Theoretical and Applied Edward Truong-Cao University of Southern California, US Soochow University, China Informatics, Poland Yashpal Singh Zheng Yulin Barbara Kraus Physical Research Laboratory, Navrangpura, Umesh Vazirani Universität Innsbruck, Austria University of California Berkeley, US University of Science and Technology of Ahmedabad, India China
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Centre for Quantum Technologies I Annual Report 2015 NRF CRP Two Grants from Singapore's Listings 8 National Research Foundation (NRF) MOE Tier 2 & 3 CQT has three research projects under its Competitive Research supported in 2015 by competitive funding from Programme support projects "Hybrid Singapore's Ministry of Education (MOE). The Quantum Technologies" ($4,325,456) led largest is "Random numbers from Quantum by Christian Kurtsiefer and "Space Based Processes" ($$9,931,731) involving 13 PIs led Quantum Key Distribution" ($6,059,084) by Valerio Scarani. The other two projects are led by Alexander Ling. "Dynamics of coherent dipole-dipole energy MONEY MATTERS transport of Rydberg excitations" ($650,201) led by Wenhui Li and "Controlling Quantum Matter: Dipolar Molecules in Optical Lattices" ($616,711) led by Kai Dieckmann.
Expenditure in 2015 Manpower Other Equipment TOTAL FQXi The US-based Foundational 8,050,102 4,806,017 1,700,298 14,556,417 Questions Institute (FQXi) supports Core a joint project by CQT and the Adam Mickiewicz University in Poland on the Stakeholder support "Operational and information theoretic External meaning of contextuality" (USD 98,900) CQT's operations are supported by its stakeholders through led by Dagomir Kaszlikowski. Dagomir direct funding and other contributions. Two major awards of core NRF CRP 764,052 590,779 152,807 1,507,638 also holds an FQXi mini-grant "Short film funding have been made: 'Three men and the Bell'” (USD 2,500). MOE Tier 2 & 3 946,398 466,751 149,230 1,562,379 2014: $36.9 million from Singapore's National Research Foundation to fund core operations FQXi 29,963 20,447 - 50,410 NRF Fellowship Computer scientist Troy Lee 2007: $158 million from Singapore's National Research is funded by a five-year Fellowship ($2,710,660) Foundation and Ministry of Education to establish the NRF Fellowship - 43,761 5,313 49,074 from Singapore's National Research Foundation. Centre and fund its operations for up to ten years Portions of the grant are managed by the Nanyang The John Templeton Foundation 50,956 24,082 - 75,038 Technological University. CQT is an autonomous research centre hosted by the National 9,841,4721 5,951,837 2,007,648 17,800,956 University of Singapore, with additional staff and facilities at Total the Nanyang Technological University (NTU). Support from the universities includes provision of building space, administrative The John Templeton Foundation staff and contributions to PI salaries commensurate with the PI's A grant supports the project service to the university. "Occam's Quantum Mechanical For a listing of all current grants, see Razor" (USD 246,100 ) led by Mile Gu http://www.quantumlah.org/main/funding until December 2017.
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Centre for Quantum Technologies I Annual Report 2015 8 Listings
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Centre for Quantum Technologies I Annual Report 2015 Centre for Quantum Technologies National University of Singapore S15 #03-18 Science Drive 2 Singapore 117543