Transfer processes in a metal with hot electrons excited by a laser pulse

Abstract

Ultrashort laser pulses are widely used in technological processes. A metal irradiated by ultrashort laser pulses is transferred to a two-temperature (2Т) state where the electron temperature is above the temperature of the ion subsystem. The theory of interaction of ultrashort laser pulses with metals includes the description of the thermal conductivity in 2Т states as an important component. This work is devoted to the solution of a serious problem of the determination of the 2Т thermal conductivity. To this end, a technique for the solution of the kinetic equation at temperatures comparable with the Fermi energy is developed for the high-temperature region of the phase diagram. Furthermore, quantum molecular dynamics (QMD) simulation of 2Т ion configurations is performed and the electrical resistivity of these configurations is calculated by the Kubo–Greenwood (QMD–KG) formula. The data calculated by the QMD–KG formula are compared to those obtained with the kinetic equation.