Demonstration of chalcogenide glass racetrack microresonators

Abstract

We have demonstrated what we believe to be the first chalcogenide glass racetrack microresonator using a complementary metal-oxide semiconductor-compatible lift-off technique with thermally evaporated As[subscript 2]S[subscript 3] films. The device simultaneously features a small footprint of 0.012 mm×0.012 mm, a cavity Q (quality factor) of 10,000, and an extinction ratio of 32 dB. These resonators exhibit a very high sensitivity to refractive index changes with a demonstrated detection capability of ΔnAs2S3=(4.5×10[superscript −6] ±10%) refractive index unit. The resonators were applied to derive a photorefractive response of As[subscript 2]S[subscript 3] to λ=550 nm light. The resonator devices are a versatile platform for both sensing and glass material property investigation.