Improving optomechanical gyroscopes by coherent quantum noise cancellation processing

Coherent quantum noise cancellation (CQNC) method is used to beat standard quantum limit (SQL) for improving the per-formance of quantum optomechanical gyroscopes. The protocol for realizing CQNC is achieved by constructing an effectivenegative mass mechanical oscillator, which is simulated by an ancillary cavity. This oscillator shows an antiresponse relativeto that of a real mechanical oscillator. Thus, the optomechanical back-action noise is counteracted or restrained, and we couldincrease our signal by increasing the coupling strength without increasing the noise.