Dynamic mode decomposition of nonequilibrium electron-phonon dynamics:accelerating the firstprinciples real-time Boltzmann equation  

作　　者：Ivan Maliyov Jia Yin Jia Yao Chao Yang Marco Bernardi 

机构地区：[1]Department of Applied Physics and Materials Science,California Institute of Technology,Pasadena,CA 91125,USA [2]Applied Mathematics and Computational Research Division,Lawrence Berkeley National Laboratory,Berkeley,CA 94720,USA [3]Department of Physics,California Institute of Technology,Pasadena,CA 91125,USA

出　　处：《npj Computational Materials》2024年第1期1970-1977,共8页计算材料学(英文)

基　　金：supported by the U.S.Department of Energy,Office of Science,Office of Advanced Scientific Computing Research,and Office of Basic Energy Sciences,Scientific Discovery through Advanced Computing(SciDAC)program under Award No.DESC0022088;supported by the U.S.Department of Energy,Office of Science,Office of Basic Energy Sciences,and Fuels from Sunlight Hub under Award DE-SC0021266.

摘　　要：Nonequilibrium dynamics governed by electron–phonon(e-ph)interactions plays a key role in electronic devices and spectroscopies and is central to understanding electronic excitations in materials.The real-time Boltzmann transport equation(rt-BTE)with collision processes computed from first principles can describe the coupled dynamics of electrons and atomic vibrations(phonons).Yet,a bottleneck of these simulations is the calculation of e–ph scattering integrals on dense momentum grids at each time step.Here we show a data-driven approach based on dynamic mode decomposition(DMD)that can accelerate the time propagation of the rt-BTE and identify dominant electronic processes.We apply this approach to two case studies,high-field charge transport and ultrafast excited electron relaxation.In both cases,simulating only a short time window of~10%of the dynamics suffices to predict the dynamics from initial excitation to steady state using DMD extrapolation.Analysis of the momentum-space modes extracted from DMD sheds light on the microscopic mechanisms governing electron relaxation to a steady state or equilibrium.The combination of accuracy and efficiency makes our DMD-based method a valuable tool for investigating ultrafast dynamics in a wide range of materials.

关 键 词：materials DYNAMICS PHONON 

分 类 号：O17[理学—数学]