All-optical probe of coherent spin waves

Abstract

A novel all-optical technique to measure the dynamic magnetic properties of microstructures is presented. The key element of the approach is the temperature dependence of the anisotropy, that allows to use the heat from an absorbed laser pulse to generate an anisotropy field pulse. Time-domain measurements on the consequently excited precision give quantitative information on the anisotropy, switching, and damping phenomena of small magnetic structures. Furthermore, it is demonstrated that due to the nonuniform character of the excitation standing spin waves can be excited, allowing for the study of spin-wave dispersion.