We report the experimental realization of magneto-optical coupling between whispering-gallery modes in a germanate (56GeO2-31PbO9Na2O-4Ga2O3) microspherical cavity due to the Faraday effect. An encapsulated gold conductor heats the resonator and tunes the quasitransverse electric (TE) and quasi-transverse magnetic (TM) polarized modes ...
We report the experimental realization of magneto-optical coupling between whispering-gallery modes in a germanate (56GeO2-31PbO9Na2O-4Ga2O3) microspherical cavity due to the Faraday effect. An encapsulated gold conductor heats the resonator and tunes the quasitransverse electric (TE) and quasi-transverse magnetic (TM) polarized modes with an efficiency of 65 fm/V at a peak-to-peak bias voltage
of 4 V. The signal parameters for a number of heating regimes are quantified to confirm sensitivity to the generated magnetic field. The
quasi-TE and quasi-TM resonance frequencies stably converge near the device’s heating rate limit (equivalently, bias voltage limit) in order
to minimize inherent geometrical birefringence. This functionality optimizes Faraday rotation and thus enables the observation of subsequent magneto-optics.