Strain-induced tunable dual-bottle-shaped optical microresonator

Opt Lett. 2019 Dec 15;44(24):6017-6020. doi: 10.1364/OL.44.006017.

Abstract

We present a novel dual-bottle microresonator with a high Q-factor exceeding 107. Such a resonator consists of two lateral resonators and one central resonator. The maximum diameter of the lateral resonator is ∼180µm, and the central diameter is 124.91 µm. Characteristics of the whispering gallery mode spectra are investigated and explained by the microbottle resonance, mode interference, and scattering effects. Strain-tuning sensitivity varies from 0.126 to 1.7 pm/µε when a tapered fiber is placed at the resonator's different positions. With a coupled area at the middle of the central resonator, the highest, to the best of our knowledge, strain sensitivity of 1.7 pm/µε, which is higher than previously reported solid microresonator strain sensors, is achieved.