Optimized optomechanical crystal cavity with acoustic radiation shield

摘要

We present the design of an optomechanical crystal nanobeam cavity that combines finite-element simulation with numerical optimization, and considers the optomechanical coupling arising from both moving dielectric boundaries and the photo-elastic effect. Applying this methodology results in a nanobeam with an experimentally realized intrinsic optical Q-factor of 1.2 x 106, a mechanical frequency of 5.1 GHz, a mechanical Q-iactor of 6.8 x 105 (at T=10K), and a zero-point-motion optomechanical coupling rate of g= 1.1 MHz.