Transient Grating Generation of Ultrafast Surface Magneto-elastic Waves

摘要

We present a simple experimental approach to generating and detecting surface-propagating magneto-elastic waves. Using the ultrafast optical transient grating geometry, we drive in-plane propagating surface acoustic waves which couple to, and resonantly drive, magnetization precession in thin magnetic films. The optical approach provides for the real-time detection of both elastic wave transients as well as the tightly coupled magnetization precession in independent detection channels and thus reveals the tight coupling between the two when an appropriate magnetic field is applied. We discuss the experimental geometry and resulting linear magneto-elastic responses. We briefly touch upon nonlinear magnetoelastic properties, which is the focus of our current work.