We present a novel locking scheme for active length-stabilization and frequency detuning of a cavity optomechanical device based on the optical spring effect. The error signal is generated by utilizing the position measurement of a thermally driven intra-cavity nanomechanical device and employing its detuning-dependent frequency shift caused by the dispersive coupling to the cavity field. The scheme neither requires external modulation of the laser or the cavity nor does it demand for additional error signal readout, rendering its technical implementation rather simple for a large variety of existing optomechanical devices. Specifically, for large-linewidth microcavities or in situations where other locking schemes appear unfavorable conceptually or are hard to realize technically, the optical spring lock represents a potential alternative for stabilizing the cavity length. We explain the functional principle of the lock and characterize its performance in terms of bandwidth and gain profile.

中文翻译：

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基于光学弹簧效应的腔体光机锁定方案

我们提出了一种新颖的锁定方案，用于基于光学弹簧效应的腔体光机械装置的主动长度稳定和频率失谐。误差信号是通过利用热驱动腔内纳米机械器件的位置测量并利用其与腔场的色散耦合引起的失谐相关频移来生成的。该方案既不需要对激光器或腔进行外部调制，也不需要额外的误差信号读出，使其技术实现对于大量现有的光机械设备来说相当简单。具体来说，对于大线宽微腔或其他锁定方案在概念上显得不利或在技术上难以实现的情况，光学弹簧锁代表了稳定腔长的潜在替代方案。我们解释了锁的功能原理，并根据带宽和增益曲线描述了其性能。