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Another Nobel Prize for Optics OCTOBER 2018 NEWSLETTER C O M M I S S I O N I N T E R N A T I O N A L E D ’O P T I Q U E · I N T E R N A T I O N A L C O M M I S S I O N F O R O P T I C S Another Nobel Prize for Optics ICO celebrates 2018 The Nobel Prize in Physics 2018 has Nobel Prize in Physics been awarded to scientists belonging to the Optics and Photonics community "for awarded to well-known groundbreaking inventions in the field of laser laser technologies: physics". optical tweezers and Arthur Ashkin received one half of the prize chirp pulse "for the optical tweezers and their application to biological systems". This research began amplification. immediately after the invention of the laser, when he experimented with the interaction of laser fields and small particles. Dr. Ashkin and colleagues reported from the first observation on the possibility of using a highly focused beam of light to capture microscopic particles in 3D. They managed to move transparent beats, which are drawn into the point with the highest light intensity. This was the birth of the “optical tweezers”. Arthur Ashkin quickly realized that the laser is great for holding and moving small objects, just like the Tractor Beam in the Star Prof. Donna T. Strickland (Canada) former member of the Trek series. ICO bureau, is the third woman in History that has been Of particular importance is that living objects awarded the Nobel Prize in Physics. can be moved without contact. Arthur Ashkin initiated a new area of application for his orders of magnitude. This low-intensity, method, namely biological systems, such as frequency-chirped optical pulse is then amplified bacteria, viruses, living cells, or even proteins in a chain of optical amplifiers up to, almost, the and DNA. The optical tweezers allow to study damage threshold of the amplifiers. Lastly, this the mechanical properties of molecular motors. high-energy pulse is compressed by a second In recent years, many researchers have advanced passive delay line. In this way, the pulse duration the method of observing, turning and stretching is shortened again to fs values, while keeping the small objects without touching them. The in vivo pulse energy. The achievement of such high- mapping of the refractive index and the elasticity intensity optical pulses has opened new is important for elucidating the inner workings perspectives for studying extreme states of matter of cells. One of the latest ideas is the digital and for a new type of inertial thermonuclear holographic optical tweezer, in which thousands fusion. Another relevant applications are high- of tweezers work simultaneously to separate harmonic generation for attosecond science and unhealthy blood cells from healthy ones, which the acceleration of charged particles up to about could be useful in the fight against malaria. 1 GeV over a distance of only 1 cm. It is worth mentioning that fs lasers are currently used for G. Mourou and D. Strickland have been micro-machining metallic materials or for Arthur Ashkin (USA, top image) and also recognized “for their method of generating LASIK procedure to treat myopia and Gérard Mourou (France, bottom high-intensity, ultra-short optical pulses”. The astigmatism. Under the initiative of Gérard image) have been awarded the Nobel CPA technique presently allows increasing the Mourou, the so-called Extreme Light Initiative Prize in Physics 2018 for the energy and hence the peak intensity of (ELI) was launched in Europe to construct three invention of optical tweezers and femtosecond (fs) laser pulses 5 orders of large research centers located respectively in chirped pulse amplification, magnitude. Before this invention, high values Check Republic, Hungary and Romania. respectively. Ashkin received ½ of were hampered by the damage occurring in the the price and Mourou shares ½ with chain of optical amplifiers. In CPA, a pulse is Jürgen Czarske Donna Strickland (Canada) first stretched, decreasing the beam intensity by Orazio Svelto ICO NEWSLETTER No. 117 OCTOBER 2018 Petawatt laser first shot by the King of Spain Prof. Luis Roso is the Last 18th September, Their Royal a fully operational facility and an international director of the CLPU: Highnesses, the King and the Queen of Spain benchmark infrastructure example of the success presided over the commissioning of the first of the collaboration between public the Center of Ultrashort Spanish petawatt laser - called VEGA - in the administrations and researchers from the Laser Pulses in Pulsed Lasers Center (CLPU) facility in university. Thanks to the versatility of its design, Salamanca (Spain) Salamanca (Spain) . They were accompanied by VEGA has potential impact in many disciplines the current Spanish Minister of Science, and fields such as plasma physics, particle Innovation and Universities, Pedro Duque, and acceleration, physics at extreme intensities, the director of CLPU, professor Luis Roso, laboratory astrophysics, etc.; thus contributing among other authorities. VEGA is one of only to the development of the scientific ecosystem three petawatt lasers in the world capable of of Salamanca. being fired once per second. With this state-of- the-art equipment, the CLPU becomes a center The goal of CLPU is to offer state-of-the-art of international reference in scientific and technology to national researchers as technological research in the field of intense international. Therefore, although the CLPU pulsed lasers. does its own research in support of scientific- This facility is the result of the collaboration technical development of high-intensity lasers, is agreement between the Spanish Government, primarily a center of users. To this unique the local administration of Castilla-León (Spain) profile of leading research, the facility has and the University of Salamanca (Spain). The developed two other strategic lines: innovation three organizations have deeply collaborated and knowledge transfer (promoting public- since the creation of the consortium that private collaboration with companies in the field manages the design, construction, infrastructure of health, safety road and the aeronautical equipment and operation, whose financing sector, among others); and disclosure (focused amounts to more than twenty millions of euros primarily on information to society and in the for investments. The special architecture of the promotion of scientific vocations). The CLPU facility allows the researchers to have three and its VEGA petawatt laser, co-financed by the different outputs that can be synchronized: ERDF Funds, are located in the Science Park of VEGA-1 of 20 terawatts, VEGA-2 of 200 the University of Salamanca, which this year terawatts and VEGA-3, of one petawatt. commemorates its eighth centenary. Although experiments with VEGA-2 have already been carried out this year, the operation Luis Roso of VEGA-3 makes the Pulsed Lasers Center into (CLPU Director) Right: His Royal Highness, the King of Spain, in the presence of Queen Letizia, pushes the button for the first shot of the petawatt VEGA laser in CLPU facility, last 18th September. The photos are a courtesy of CLPU in Salamanca (Spain). No. 117 OCTOBER 2018 ICO NEWSLETTER th ICO bureau meets in Delft for 70 anniversary The first meeting of the ICO bureau was held in Delft in 1948. For this anniversary, the current board met in Delft in 2018 and took a symbolic photo in front of the same building as 70 years ago. Photo of members of the current ICO board in front of the same building, where the first ICO bureau took place in 1948. From left to right, in the top row: P. Urbach, J. Harvey, L. Sirko, J. Howell. Middle row: F. Höller, E. Rosas, G. von Bally, Q. Gong, J. Czarske, M. Zghal. Bottom row: C. Londoño, R. Ramponi, Y. Arakawa, H. Michinel, N. Kundikova, S. Park. In the column on the left, the original photo of the 1948 meeting is shown. With the goal of celebrating the 70th anniversary The ICO Galileo Galilei award 2018, chaired by of the first ICO bureau meeting, the board of Prof. Dr. Nataliya Kundikova has been given to directors of ICO met in Delft last 8th October in Dr. Debabrata Goswami, from Indian Institute Delft (The Neteherlands) and took a of Technology, India, for extensive contri- commemorative photo in front of the same butions to the frontiers of interdis-ciplinary building where the first ICO meeting took place research that involved both theoretical and in 1948. 70 years have passed and ICO has experimental developments in the fundamental grown and expanded, as it was commented in aspects of femtosecond laser-matter interactions the previous newsletter dedicated exclusively to under comparatively diffi-cult circumstances. this anniversary. The Gallieno Denardo award 2018 has been Several issues from the agenda were approved by also approved and, following the tradition, the the board and reports from the ICO committees winner of the 2019 edition will be announced were presented. Among the most important, the during the ICTP winter school in Trieste, Italy, ICO awards for 2018. The ICO-IUPAP prize next February. The next meeting of the ICO 2018, chaired by Prof. Dr. Adrian Podoleanu, bureau will take place in Carthage (Tunis), has been awarded to Dr. Can Bayram, from the during the celebration of the optical meeting university of Illinois, who revolutionized the way OPTISUD-2019, from 1st to 5th September, graphene has been employed, making major 2019. The workshop will be organized by ICO contributions to III-V photonic devices. vice-president Prof. Dr. Mourad Zghal. ICO NEWSLETTER No. 117 OCTOBER 2018 EOS celebrated its biannual meeting Prof. Humberto The European Optical Society, an international OCT, surface plasmons, new materials for solar society member of ICO, has celebrated its energy conversion or silicon nanophotonics, Michinel from the biannual congress, the EOSAM-2018 in the among others.
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