title: Time-dependent Kohn-Sham theory with memory.
abstract: In time-dependent density-functional theory, exchange and correlation (xc) beyond the adiabatic approximation can be described by viscoelastic stresses in the electron liquid. In the time domain, the resulting velocity-dependent xc vector potential has a memory containing short- and long-range components, leading to decoherence and energy relaxation. We solve the associated time-dependent Kohn-Sham equations, including the dependence on densities and currents at previous times, for the case of charge-density oscillations in a quantum well. We illustrate xc memory effects, clarify the dissipation mechanism, and extract intersubband relaxation rates for weak and strong excitations.
authors.affiliation: Department of Physics and Astronomy, University of Missouri, Columbia, Missouri 65211, USA.
authors.forename: H O
authors.initials: HO
authors.lastname: Wijewardane
authors.forename: C A
authors.initials: CA
authors.lastname: Ullrich