Hamburg Prize for Theoretical Physics

In cooperation with the Wolfgang Pauli Centre (WPC) at Universität Hamburg and DESY and the two Clusters of Excellence CUI: Advanced Imaging of Matter and Quantum Universe at Universität Hamburg, the Joachim Herz Foundation awards the “Hamburg Prize for Theoretical Physics” for outstanding research achievements in the field of Theoretical Physics.
The prize, which is endowed with €137,036, is linked to a stay of the highly qualified scientist in Hamburg. This will initiate joint research activities and, in particular, support interaction with young scientists at Science City Hamburg Bahrenfeld, for example in the context of lectures or seminars.
Eligible to nominate for the award are the physical research institutes in Hamburg, the board of the German Physical Society, and the previous award winners as well as the jury members.
Previous laureates
The previous laureates are Prof. Maciej Lewenstein (2010), Prof. Peter Zoller (2011), Prof. Shaul Mukamel (2012), Prof. Chris H. Greene (2013), Prof. Antoine Georges (2014), Prof. Dr. Ignacio Cirac (2015), Prof. Mikhail Katsnelson (2016), Prof. Andrew Millis (2017), Prof. Hirosi Ooguri (2018),
Prof. Matthias Troyer (2019), Prof. Valery Rubakov (2020), Prof. Eugene Demler (2021), and Prof. Nicola Spaldin (2022).

Nicola Spaldin
Nicola Spaldin (born 1969) studied chemistry and geology at the University of Cambridge and showed an interest in the intersection between physics, chemistry and materials research from an early stage. After completing her PhD at the University of California/Berkeley in 1996, she worked as a postdoctoral researcher at Yale University/New Haven before serving as Assistant Professor and later Associate Professor at the University of California/Santa Barbara. She subsequently became a Full Professor at the same institution in 2006. She has been Professor of Materials Theory in the Department of Materials at ETH Zürich since 2011.
Multiferroics: theoretical predictions and experimental breakthrough
In 1997, a colleague at Yale University made a casual comment to Nicola Spaldin during a coffee break that would come to consume her: it’s a pity that there are no ferroelectric materials that also have ferromagnetic properties, i.e. that can also be magnetised. Using quantum theory and computer models, she spent the next few years investigating the conditions that must be fulfilled in order for crystalline chemical compounds to be both electrically polarisable and magnetisable. In 2000, she published a ground-breaking article entitled “Why are there so few magnetic ferroelectrics?” The key finding of this work was the fact that ferromagnetism and ferroelectricity are not fundamentally incompatible. We simply need to arrange the right atoms in a suitable crystal structure to obtain these types of multiferroic materials.
With the aid of density functional theory – a numerical formalism used to calculate the electron states in complex many-particle systems, which Spaldin had to extend slightly for this work – she concluded that metal oxide compounds containing two specific metal atoms in addition to oxygen atoms could have both ferroelectric and ferromagnetic properties. Together with her collaborators, she began to create chemical compounds of this kind in the lab in order to test her predictions. The breakthrough came in 2003 in cooperation with the group of Ramamoorthy Ramesh at University of California/Berkeley: thin films of bismuth ferrite were grown in the laboratory and shown to be multiferroic. After the work was published in the journal “Science”, the number of publications on the topic skyrocketed. The material is now one of the most intensively researched multiferroics.
Performance enhancement and optimisation
Nicola Spaldin and her group at the ETH Zurich have been driving the development of this new material class since 2010. As the interaction between theory and experiment plays an important role in this process, she operates her own laboratory for the synthesis of multiferroics and benefits from access to supercomputers and physical measuring instruments for material characterisation at major Swiss research centres such as the Paul Scherrer Institute.
In addition to multiferroics, the British scientist is also interested in other innovative materials with exciting properties. She uses her expertise for the theoretical description of interactive many-particle systems to better understand how superconductors function, among other things. Her vision is to produce superconducting materials that no longer require costly cooling to conduct electricity without loss.

Eugene Demler
The Russian-American researcher Eugene Demler is to receive the Hamburg Prize for Theoretical Physics 2021. Demler, who has been a physics professor at Harvard University in the USA since 2001 and will join ETH (Zurich) faculty in the Fall of 2021, works on understanding strongly correlated quantum matter from electrons in solids to dilute atomic gases to photons. His work has had a profound impact on diverse areas such as magnetism and superconductivity, many-body physics with ultracold atoms in optical lattices, nonlinear quantum optics, and pump and probe experiments in solids. The prize will be awarded to Demler in November 2021 in Hamburg.
Towards a better understanding of materials with quantum simulation
Demler is a world-renowned expert in theoretical quantum physics. Theoretical quantum physics describes how electrons, atoms and other miniscule objects behave. Among other things, Demler’s work was instrumental to the development of the field of quantum simulators based on ultracold atoms. When trying to understand complex materials, condensed matter theorists introduce simplified models, analyze them, and try to relate their results to experimentally measured properties of materials. However, even basic models are difficult to solve accurately when they involve strong interactions between particles. When theoretical results disagree with experiments, it is not clear whether this comes from not being able to solve the model accurately or from the model lacking some important features. Quantum simulators resolve this problem by creating experimental systems that emulate fundamental models of condensed matter physics. In particular, cold atom simulators use atoms arranged into periodic structures with laser beams to create artificial crystals.
Experiments done on cold atom simulators will not only allow researchers to understand the properties of paradigmatic models but will also elucidate what they are missing for describing condensed matter systems. Experiments done on cold atom simulators have already delivered new insights into the properties of materials that arise from the complex interaction of thousands of particles that obey the laws of quantum mechanics. These include quantum magnets and topological insulators, as well as superconductors, which are materials that allow resistance-free transmission of electricity.

Valery Rubakov
In recent years, research teams around the world have gained important insights into the origin of the universe. They often relied on the work of Valery Rubakov. The Russian physicist will receive this year’s Hamburg Prize for Theoretical Physics. Rubakov is chief researcher at the Institute for Nuclear Research of the Russian Academy of Sciences in Moscow and Professor at M.V. Lomonosov Moscow State University.
The question of what we and the world around us are made of has always driven humankind. Our matter is built up of atoms, which again consist of protons, neutrons, and electrons. In the classical standard model of particle physics which describes all known elementary particles and their fundamental forces with the strong and weak interaction and electromagnetism, the proton is considered as stable. Valery Rubakov challenged this assumption and developed the theory of catalysis of proton decay by magnetic monopoles, the so-called Callan-Rubakov effect. This effect suggests that a magnetic monopole would cause a decay of protons, the basic building blocks of our matter, leaving an observable footprint in the form of lighter particles such as positrons, photons, and neutrinos. Magnetic monopoles must have been created shortly after the Big Bang and theoretically still occur sporadically today.
Rubakov also provided important explanatory models for the origin of matter in the universe and disappearance of antimatter. Antimatter is a kind of mirror image of our matter. For every particle there is an antiparticle with opposite charge. When particles and antiparticles meet, they extinguish each other by emitting a flash of energy. Since our universe consists of matter, an asymmetric process must have caused an imbalance between matter and antimatter shortly after the Big Bang in the early phase of our universe. The violation of the baryon number in the standard model, which Rubakov published as early as the mid-1980s, provides an important theoretical explanation for the origin of this imbalance and is still one of the most challenging questions and a field of active research today. Today, numerous experiments in particle accelerators aim to study the properties of antimatter and thus to find indications for the origin of our universe and its expansion, which continues until today.
Matthias Troyer

This year’s Hamburg Prize for Theoretical Physics will be presented to Austrian Matthias Troyer, a professor at ETH Zurich and quantum computing researcher at software company Microsoft. He is receiving the prize for his contributions to the development of quantum Monte Carlo algorithms.
Using random numbers, these algorithms can predict how tiny particles will interact within quantum mechanical many-body systems such as atoms and molecules. As a result, Troyer is playing a key role in basic research and the ongoing development of quantum computers and superconductive materials. He is one of just a handful of leading international researchers in this field. The Joachim Herz Stiftung awards the prize in conjunction with the Wolfgang Pauli Centre (WPC) at the University of Hamburg, DESY, and the Cluster of Excellence “CUI: Advanced Imaging of Matter” at the University of Hamburg.
Hirosi Ooguri

This year’s Hamburg Prize for Theoretical Physics will be awarded to the Japanese scientist Hirosi Ooguri. Ooguri, born in 1962, is a professor at California Institute of Technology (Caltech) in Pasadena (USA). He is one of the world’s leading experts on so-called topological string theory, which addresses mathematical aspects of superstring theory – an important path towards an all-encompassing theory on the nature of our universe. Ooguri will be presented with the award on November 7, 2018 at the Hamburg Planetarium.
Ooguri´s research deals with mathematical superstring theory. Ooguri has succeeded in enabling many physical phenomena to be computed with the aid of string theory. He was able to overcome many of the major mathematical difficulties of string theory. Moreover, Ooguri’s research on the quantum mechanics of black holes continues the research of physicist Stephen Hawking, who died earlier this year.
Ooguri arrived at Caltech in 2000 as a professor for theoretical physics. He is Fred Kavli Professor and Director of the Walter Burke Institute for Theoretical Physics. Moreover, he is a principal investigator of the Kavli Institute for the Physics and Mathematics of the Universe at the University of Tokyo, and has recently been appointed President of the Aspen Center for Physics in Colorado, USA.
Ooguri has received numerous awards. He is a Fellow of the American Academy of Arts and Sciences, to name but one, and has also received the Leonard Eisenbud Prize for Mathematics and Physics from the American Mathematical Society.
Andrew Millis

This year's Hamburg Prize for Theoretical Physics, jointly awarded by the Joachim Herz Stiftung and The Hamburg Centre for Ultrafast Imaging (CUI), will be given to Andrew Millis, Professor at Columbia University in New York and Associate Director for Physical Sciences at the Simons Foundation.
The prize recognizes, the U.S. physicist for his outstanding research in condensed matter physics, a field focusing on atomic and molecular interactions in solids and liquids. His work enables calculations that predict electronic properties of materials, including electrical conductivity and the tendency to magnetism. He has made landmark discoveries in properties of superconducting materials (which can conduct electric current without losses).
While most superconductors must be cooled to extremely low temperatures to reach lossless conductivity - a time-consuming and expensive process - a few are superconducting at much higher temperatures. Millis' research has enhanced our understanding of these special materials, and his recent work may provide a path to pushing the temperature threshold for superconductivity even higher, perhaps all the way to room temperature.
Millis studied physics at Harvard University and received a PhD from the Massachusetts Institute of Technology in 1986. He then worked as a scientist at Bell Laboratories in New Jersey. In 1996 Millis was appointed professor at the Johns Hopkins University in Baltimore and three years later moved to Rutgers University in New Jersey. In 2001 he joined the physics department at Columbia University, where he served as Department Chair from 2006 - 2009. Since 2011 he has been Associate Director for Physical Sciences at the Simons Foundation, a large U.S. foundation whose mission is to advance mathematics and basic research. Starting Sept 1, 2017 he will also be co-Director of the Center for Computational Quantum Physics at the Simons Foundation's new Flatiron Institute.
Prof. Katsnelson

Prof. Katsnelson is working on the quantum mechanical many-body theory, the theory of strongly correlated systems, and the quantum theory of magnetism as well as of graphene. Katsnelson is a researcher with an extraordinary broad range of interests. His work on graphene has greatly profited from his versatile expertise and methodology. Graphene has many remarkable characteristics and can be applied to very different fields of science.
Mikhail Katsnelson published his first scientific papers at the age of 17 and started his academic career in the former Soviet Union. After passing the Master of Science examination in Theoretical Physics at the Department of Physics at Ural State University, Sverdlovsk, he received his PhD in Solid State Physics at the Institute of Metal Physics (Sverdlovsk) in 1980 and his DSc in 1985. Seven years later he was appointed to a professorship for Solid State Physics and for Mathematical Physics at Ural State University. In 2004, after spending two years in Sweden as visiting professor at Uppsala University, Radboud University in Nijmegen, Netherlands, appointed him to a professorship. He is head of the group “Theory of Condensed Matter”.
Prof. Dr. Ignacio Cirac

The recipient of the 2015 “Hamburg Prize for Theoretical Physics” is Prof. Dr. Ignacio Cirac, Director at the Max Planck Institute of Quantum Optics in Garching and head of the Theory Division.
Ignacio Cirac studied theoretical physics at the Universidad Complutense de Madrid where he received his PhD in 1991. He began his career in physics as a “Professor Titular” at the Universidad de Castilla-La Mancha where he stayed until 1996. In 1996 he became a Professor at the department of Theoretical Physics at the University of Innsbruck. Since 2001 he has been Director at the Max Planck Institute of Quantum Optics in Garching and head of the Theory Division.
Prof. Cirac develops methods to describe and control atoms, molecules and photons on the basis of quantum mechanics. His quantum physics models are particularly pioneering for the control and storage of information, which is, for instance, important for the development of quantum computers. Cirac’s methods also make major contributions to other fields like solid state physics, superconductivity and recently even the simulation of models of particle physics.
Honors and Awards (selection)
Felix Kuschenitz Preis, Austrian Academy of Sciences, 2001,
Quantum Electronics Prize, European Science Foundation, 2005,
Royal Spanish Prince of Asturias Prize, 2006,
International Quantum Communication Award, 2006, together with Professor Peter Zoller,
Frontiers of Knowledge Award in Basic Sciences, BBVA Foundation, 2009,
Benjamin Franklin Medal, Franklin Institute in Philadelphia, 2009, together with Professor Peter Zoller,
Israeli Wolf Prize and Niels Bohr Medal, 2013,
Honorary Doctor from the University of Zaragoza, 2014,
Honorary Doctor from the University of Valencia as well as the Universitat Politècnica de València, 2015.
ANTOINE GEORGES

The recipient of the 2014 Hamburg Prize for Theoretical Physics is Prof. Antoine Georges, distinguished Professor at the Collège de France and the École Polytechnique in Paris, as well as the University of Geneva. He receives the prize due to his contributions to condensed matter physics, in particular for the development of novel methods to describe strongly correlated systems.
In 1988 Prof. Georges received his PhD at the École Normale Supérieure. Due to an offer of the Princeton University, Antoine Georges has been working in the USA as a Postdoc from 1989 to 1991. With returning to France in 1991, he deepened his research regarding the condensed matter physics and later on in 2003 directed a research team at the École Polytechnique. Since 2009 he is a Professor of Condensed Matter Physics at the Collège de France. He is also working as a part-time professor at the University of Geneva.
The main focus of Prof. Georges‘ research has been on the physics of materials with strong interactions between electrons, which possess remarkable electronic properties. His contributions deepened our understanding of these materials and our ability to explain, calculate and predict their physical properties.
HONORS AND AWARDS (SELECTION)
Anatole et Suzanne Abragam Prize, Academie des Sciences, 1991
Prix Dargelos, École Polytechnique (AX), 2004
Condensed Matter Europhysics Prize for “the development and application of Dynamical Mean-Field Theory'', European Physical Society and Agilent Technologies, 2006;
together with Gabriel Kotliar, Walter Metzner, Dieter Vollhardt
Médaille d'Argent du CNRS, CNRS, 2007
Laureate of an ERC-Synergy grant, ERC, 2012;
together with Andrea Cavalleri, Dieter Jaksch and Jean-Marc Triscone.