Nonreciprocity in a rotational cavity system

We investigate a system of two coupled optical cavities driven by control and probe fields, where photon tunneling and a common rotational mirror influence the photon dynamics. The investigation explores the effects of control field power, photon tunneling strength, and the phase difference between the control fields on the probe field responses in each cavity. When the control fields in both cavities are coherent, with a phase difference and a nonzero photon tunneling strength, the system exhibits nonreciprocal behavior. Specifically, the probe field in cavity \(a_{1}\) shows a transparency window, while the probe field in cavity \(a_{2}\) exhibits absorption, with the opposite behavior observed by changing the phase difference. This asymmetry arises from the interaction between photon tunneling and phase difference, which induces asymmetric coupling between the cavities. Our findings highlight the critical role of photon tunneling and phase difference in generating nonreciprocal behavior in coupled cavity systems and provide insights into their potential application in nonreciprocal optical devices.