Power thresholds of morphology dependent induced thermal scattering in silica microresonators

Abstract

Induced thermal scattering power thresholds have been calculated as a function of size and laser pump frequency. The thermal coupling coefficients of morphology dependent resonances were estimated by asymptotic methods. The resulting power threshold is comparable with experimental observations of thresholds of Raman lasing and thermal instability in spherical silica resonators. Applications may include the remote measurement of the temperature of aerosol droplets and the stabilization of microcavity lasers against thermal oscillations and temperature deviations on microcavity. A silica resonator can be used as an IR sensor, as well as an additional tool for precisely measuring the thermal conductivity and heat capacity of a target in a microsphere by calculating of the thermal shifts of eigenfrequencies in spectra of nonlinear scattering.