  With the goal of pushing Spintronic devices towards faster and faster
timescales, we demonstrate, using ab-intio time-dependent density functional
theory simulations of bulk Heusler compounds subject to ultrashort intense
laser pulses, that the local magnetic moment can increase or decrease in a few
femtoseconds. This speed is due to the all optical nature of the process, which
transfers spin moment from one sublattice to another. This transfer depends on
easily tunable laser parameters. By comparing the spin dynamics of a variety of
Heusler (or half-Heusler) compounds, we demonstrate that the density of states
explains the observed moment transfer; most the physics of inter sublattice
moment transfer is due to the flow of spin current which is governed by
availability of states above the Fermi level.
