Abstract. In our density-functional-based simulations of materials responding to femtosecond-scale laser pulses, we have observed a potentially useful phenomenon: the excited electrons automatically equilibrate to a Fermi–Dirac distribution within ~100 fs, solely because of their coupling to the nuclear motion, even though the resulting electronic temperature is one to two orders of magnitude higher than the kinetic temperature defined by the nuclear motion. Microscopic simulations like these can then provide the separate electronic and kinetic temperatures, chemical potentials, pressures, and nonhydrostatic stresses as input for studies on larger lengths and timescales.

Print publication: Issue 48 (2 December 2009)
Received 30 July 2009, in final form 18 October 2009
Published 6 November 2009