Thermal mode decomposition method for microresonator thermal parameters estimation

The absorption of optical power in high-Q microresonators leads to thermal effects, that strongly affect quantum and nonlinear processes. To take these effects into account, rate equations with effective thermal parameters are commonly used. Despite the convenience and simplicity of this approach, its applicability for a certain range of microresonator parameters may not be accurate enough. In our work, we compared various methods for determination of the effective thermal parameters for different resonator structures: the microring and microtorus resonator. As a result, we propose an original and effective method for determining the effective thermal parameters of microresonators based on thermal mode decomposition that considers various thermal relaxation processes. The proposed method agrees better with both direct numerical simulation and well-known theoretical formulas over the entire range of microresonator parameters, in contrast to the classical approach.