Temperature-Insensitivity PDMS Coated Silica Microsphere

This article presents a high-Q resonator that is temperature-insensitive and operates based on the Whispering Gallery Mode (WGM) pattern. Due to the negative thermal-optic coefficient of PDMS, which is one order of magnitude larger than that of silica microspheres, we uniformly coated a small amount of PDMS on the surface of silica microspheres to obtain a temperature-insensitive resonator while maintaining a high Q value. The experimental results demonstrate a Q-factor of 10
⁸
for the resonant cavity, with a temperature crosstalk of only 0.4654pm/°C.