Investigation of ferromagnetic resonance by the inelastic light scattering technique

Abstract

The ferromagnetic resonance at X-band microwave frequency is detected by the inelastic light scattering technique. The spin precession generates frequency shifted light contained in the direct laser beam which is observed either in transmission or reflection. Discrimination from the unshifted light is done with a tandem 4+2 pass Fabry-Perot interferometer. The microwave excitation is performed with conventional waveguide techniques and with planar microwave structures. YIG platelets, epitaxial YIG films on GGG substrate, iron borate platelets and single crystal iron films on GaAs substrates are investigated. The method is very sensitive; under favourable conditions even the thermally excited uniform precession (i.e. no microwave excitation) can be detected. Furthermore the technique allows spatially resolved recording of the FMR intensity.