Two-Dimensional Propagation of a Photoinduced Spin Wave Packet

TL;DR

This study demonstrates the two-dimensional propagation of photoinduced spin wave packets in a magnetic garnet, revealing directional dependence and confirming theoretical dispersion relations through experimental observation.

Contribution

It presents the first experimental observation of 2D propagation of photoinduced spin waves in a garnet, including their directional dependence and dispersion characteristics.

Findings

Detection of backward volume magnetostatic waves in two directions

Frequency variation of BVMSWs depends on propagation direction

Experimental results align with theoretical dispersion relations

Abstract

We report the two-dimensional propagation of photoinduced spin wave packets in Bi-doped rare-earth iron garnet. Spin waves were excited nonthermally and impulsively by a circularly polarized light pulse via the inverse Faraday effect. Space- and time resolved spin waves were detected with a magneto-optical pump-probe technique. We investigated propagation in two directions, parallel and perpendicular to the magnetic field. Backward volume magnetostatic waves (BVMSWs) were detected in both directions. The frequency of BVMSWs depends on the propagation direction. The experimental results agreed well with the dispersion relation of BVMSWs.