Theory of out-of-equilibrium ultrafast relaxation dynamics in metals

Article

关键词: ELECTRON THERMALIZATION;    NONEQUILIBRIUM ELECTRON;    GOLD;    SPECTROSCOPY;    TEMPERATURE;    LATTICE;    SYSTEM;   

DOI  :  10.1103/PhysRevB.96.174439

来源: SCIE

【 摘 要 】

Ultrafast laser excitation of a metal causes correlated, highly nonequilibrium dynamics of electronic and ionic degrees of freedom, which are, however, only poorly captured by the widely used two-temperature model. Here we develop an out-of-equilibrium theory that captures the full dynamic evolution of the electronic and phononic populations and provides a microscopic description of the transfer of energy delivered optically into electrons to the lattice. All essential nonequilibrium energy processes, such as electron-phonon and phonon-phonon interactions are taken into account. Moreover, as all required quantities are obtained from first-principles calculations, the model gives a realistic and material-dependent description of the relaxation dynamics without the need for fitted parameters. We apply the model to FePt and show that the detailed relaxation is out-of-equilibrium for ps.

【 授权许可】

Free