Abstract
It is demonstrated that ferrimagnetic resonance can be applied to induce a dynamical conversion of optical modes in a magnetic garnet film. The fundamental and first-harmonic Fourier components of the converted mode are measured as a function of frequency and bias field; a dynamical conversion efficiency of 2% is obtained. The amplitude of the first harmonic depends very critically on the orientation of the magnetization with respect to the film normal. The results are confirmed by calculations on the basis of Faraday rotation and Cotton–Mouton effect.