Magnetization switching in GdFeCo induced by dual optical excitation

Abstract

We investigate the impact of optical excitation using two interfering ultrashort pulses on the process of all-optical magnetization reversal. Employing optical time-resolved techniques, we observe distinct differences in the process of light-induced magnetization switching in GdFeCo alloy when triggered with two noncollinear ultrashort pulses as compared to single-pulse excitation. Specifically, we find that the threshold fluence required for magnetization switching is significantly reduced when excited with interfering pulses compared to noninferometric excitation. We further discuss the potential modification of the magnetic dynamics of electrons as a result of optical excitation with interfering light as a possible explanation for the observed trends.