Single laser pulse induced dynamic magnetization reversal mechanism of perpendicularly magnetized L1 FePt films

Abstract

In order to measure photoinduced dynamic magnetization reversal by single laser pulse, alternating magnetic field is synchronized with the femtosecond laser pulse such that the magnetization state is reset before each single laser pulse. For perpendicularly magnetized L10 FePt films, the dynamic magnetization reversal process is accompanied by the nucleation of reversed domains and the barrierless transient domain wall motion at low magnetic fields and subsequent pinned domain wall motion at the switching field. The switching field does not change with the pump-probe delay time.