This year’s “Hamburg Prize for Theoretical Physics“, which is jointly awarded by the Joachim Herz Stiftung and CUI, will be given to Prof. Dr. Antoine Georges, Professor at Collège de France, École Polytechnique, and University of Geneva. The “Hamburg Prize for Theoretical Physics“ is connected with a research and teaching stay of Prof. Georges at CUI. The prize strengthens Hamburg as an international research centre and especially promotes the interdisciplinary exchange with young scientists“, says Petra Herz, Chairwoman of the Executive Board of the Joachim Herz Stiftung.
Credit: Jean-Francois Dars, CNRS
Prof. Georges` work in the field of theoretical solid state physics opens up an understanding of how the properties of materials, such as metallic or insulating oxides, are influenced by their structure and by the interactions between electrons at the atomic scale. “If you want to make progress in technologies it is important to theoretically describe materials as well as possible. Prof. Georges` theoretical models further the development of new materials“, says Prof. Andrea Cavalleri from the Max Planck Institute for the Structure and Dynamics of Matter in Hamburg.
Correlated electrons – dynamic as the Mexican wave
To understand why superconductors conduct electric current without losses, a theoretical model cannot look at each individual electron. A solid consists of roughly 10²³ particles/cm³ – a figure with 23 zeros. Therefore, it is necessary to find a description which simplifies the interplay of electrons, but at the same time captures the properties of a certain material as realistically as possible. This can be compared to a Mexican wave: To understand why the wave proceeds through a stadium and when it subsides, one cannot look at the individual behavior of each football fan. One has to observe how the fans react to external conditions like the overall atmosphere, the ongoing football match, and the behavior of the other supporters. A Mexican wave emerges only as a result of the interplay of the football fans, the “correlated“ behavior. Therefore one can only understand and predict it if external conditions are adequately taken into account and a suitable description of the interaction of the spectators is applied.
Prof. Georges` models lead to a description of properties of materials with strongly correlated electrons. In addition, his research provides important insight into the interface of theoretical solid state physics and materials science: New materials with correlated electrons, for instance, could be used in sensors, switches or other novel electronic devices.
Innovative collaboration for technological progress
High-temperature superconductivity represents a particular material property which could be applied for instance in unimaginably fast computer chips, new types of power storage or supply systems without any losses. Superconductivity means that an electric current is conducted without losses – meaning without resistance. Up to now this effect occurs only at very low temperatures of roughly -250 to -140 °C. Together with three scientists from different fields, among them Prof. Cavalleri, Prof. Georges aims to achieve superconductivity at higher temperatures, maybe even at room temperature. The corresponding project has been funded by the European Research Council since 2012.
Award combines research and education
The Hamburg “Prize for Theoretical Physics“ goes along with a perspective research and teaching stay at the University of Hamburg. “We are very much looking forward to Antoine Georges` visits at CUI. Apart from his research on superconductivity, his models for correlations of electrons in solids provide many starting-points for joint research activities in Hamburg, for instance in the field of ultracold gases“, says Prof. Dr. Klaus Sengstock, chairperson of the prize committee and spokesperson of CUI. “The students in Hamburg will particularly benefit from Prof. Georges` courses. His lectures at the Collège de France are just excellent.“
The Hamburg Prize for Theoretical Physics is worth €40,000 and was first established in 2010 by the cluster of excellence “Frontiers in Quantum Photon Science” at Universität Hamburg, which the Joachim Herz Stiftung supported. Today the Prize is awarded jointly by the Joachim Herz Stiftung and the federalcluster of excellence “CUI” at Universität Hamburg. The awards ceremony will take place during the annual CUI Colloquium at Science Campus Bahrenfeld in Hamburg between November 12th and 14th 2014.
Additional information: superconductivity – green light for electrons
Road traffic is a good example to compare normal electric conductivity with superconductivity: When all cars move at individual speed, they will impede each other. Such electric resistance also exists in conducting materials where currents cannot flow without hindrance. However, when all cars are joined up in a procession, they can all be driven with the same speed. As they can now be driven without hindrance, no traffic jams will arise and all cars will advance more rapidly and economically. Superconductivity enables the same process in materials: Electrons are strongly correlated and move without hindrance.