Modeling of Ultrafast Heat- and Field-Assisted Magnetization Dynamics in FePt

FePt is among the most widely used materials for data-storage technology, and recent experiments surprisingly suggest the possibility of all-optical control of its magnetization--without any external magnetic field. Sorting out the electronic temperature in the presence of heating from a laser burst, and any helicity dependence of the switching, is essential. Using a high-temperature micromagnetic model, the authors study ultrafast magnetization reversal in thin films of FePt exposed to laser pulses with linear and circular polarizations, to begin to clarify the critical details.