For his ground breaking research in the field of Warm Dense Matter Professor Michael Bonitz from the Institute for Theoretical Physics and Astrophysics of Kiel University (CAU) receives the John Dawson Award for Excellence in Plasma Physics Research 2021. With this award the American Physical Society (APS) every year recognizes a particular recent outstanding achievement in plasma physics research. This year, the citation reads “For developing Monte Carlo methods that overcome the fermion sign problem, leading to the first ab initio data for an electron gas under warm dense matter conditions.” Bonitz shares this award with his former Ph.D. students Dr. Tim Schoof (Deutsches Elektronen Synchrotron, DESY), Dr. Tobias Dornheim (Center for Advanced Systems Understanding, CASUS, Görlitz), and Dr. Simom Groth (McKinsey & Company), as well as Prof. Dr. William Matthew Colwyn Foulkes (Imperial College London), Dr. Fionn D. Malone (QC Ware), and Dr. Travis Sjostrom (Los Alamos National Laboratory). The award consists of $5,000 and an allowance for registration and travel to the Division of Plasma Physics Annual Meeting.
Warme Dense Matter denotes and exotic state of Matter at extreme pressure and low to moderate temperatures, as they occur in the interior of stars and planets as well as in the core of the Earth. Similar extreme conditions are also being produced in the laboratory, with high power lasers and free electron lasers, such as the European XFEL between Hamburg and Schenefeld (Schleswig-Holstein). There different materials are being heated, compressed, or strongly excited. The theoretical description of these states of matter is very difficult, because many effects such as the Coulomb interaction of the charged particles, quantum and spin effects of the electrons, and strong excitation have to be taken into account simultaneously. As a consequence, well established theories and computer models fail.
During the past ten years the Kiel plasma physicists, together with their partners from the U.K. and the U.S., achieved a breakthrough. They developed novel quantum Monte Carlo simulations the combination of which ultimately made it possible to accurately predict the behavior of the electrons under all relevant conditions. The computed data have already been incorporated into more complex simulations, such as density functional theory simulations — the main workhorse in the modeling of atoms, molecules and solids. Moreover, during the last three years, the researchers were able to make numerous theoretical predictions regarding the optical, transport and collective electronic properties, of warm dense matter, the verification of which is subject of future experiments. The scientific works of the team received already more than 1000 citations and many prizes for young researchers.
Dr. Tim Schoof, meanwhile a research scientist at DESY Hamburg in the area Research with photons/Scientific Computing), in his Ph.D thesis in the group of Professor Michael Bonitz, achieved the first numerical implementiation of the novel Configuration Path Integral Monte Carlo approach (CPIMC) and its application to the uniform electron gas. This work laid the basis for the success of the research team. Dr. Simon Groth, now a consultant at McKinsey & Co., continued the CPIMC developments in his Master thesis and Ph.D thesis in the group of Michael Bonitz. Dr. Tobias Dornheim,presently a research scientist in the area of warme dense matter at the Center for Advanced Systems Understanding, Görlitz, developed, in his Ph.D thesis in the group of Michael Bonitz, Permutation Blocking Path Integral Monte Carlo and various original solutions for the Ab initio computation of thermodynamic properties of warm dense matter. More recently he has developed numerous additional innovative concepts which include the computation of the dynamic structure factor, the local field correction and the linear and nonlinear density response of the electron gas which have significantly advanced the field of warm dense matter.