Analysis of thermal stabilization of whispering gallery mode resonance

Stabilization of whispering gallery mode (WGM) resonance wavelength by the thermal mechanism, originally presented by Carmon et al. [Optics Express 12 (2004) 4742–4750], is analyzed. Analytical expressions are derived for the resonance peak broadening and roll-off ramp rate in the pump-in wavelength scan. Also obtained are simple expressions for the resonance wavelength fluctuations due to ambient temperature changes and mode power fluctuations. The thermal mechanism does not pass these perturbations onto the WGM resonance wavelength, providing a robust stabilization scheme.