In this letter, a torsional optomechanical resonator for torque sensing and torsional mechanical frequency mixing is experimentally demonstrated. The torsional mechanical resonator is embedded into a split optical racetrack resonator, which provides high sensitivity in measuring torsional mechanical motion. Using this high sensitivity, torsional mechanical frequency mixing is observed without regenerative mechanical motion. The displacement noise floor of the torsional mechanical resonator is 50 fm/Hz0.5, which demonstrates a resonant torque sensitivity of 3.58 × 10−21 N m/Hz0.5. This demonstration will benefit potential applications for on-chip RF signal modulation using optical mechanical resonators.

中文翻译：

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光机械谐振器中的扭频混合和传感

在这封信中，通过实验演示了用于扭矩传感和扭转机械频率混合的扭转光机械谐振器。扭转机械谐振器嵌入到分体式光学跑道谐振器中，在测量扭转机械运动时提供高灵敏度。使用这种高灵敏度，可以在没有再生机械运动的情况下观察扭转机械频率混合。扭转机械谐振器的位移噪声基底为 50 fm/Hz0.5，这表明谐振扭矩灵敏度为 3.58 × 10−21 N m/Hz0.5。该演示将有利于使用光学机械谐振器进行片上 RF 信号调制的潜在应用。