Tunable optical bistability in multi-mode optomechanical system

Optical bistability has been studied theoretically in a multi-mode optomechanical system with two mechanical oscillators independently coupled to two coupled cavities. It is found that the multi-mode optomechanical system allows one to control the optical bistability in a much more flexible way. Specifically, the bistable behavior of the mean intracavity photon number in one cavity can be tuned by the strength and frequency of the pump laser beam driving another cavity. Meanwhile, it is also found that the coupling between the two cavities and the coupling between mechanical oscillators and cavities can effectively affect the optical bistability behavior in a sensitive manner. Moreover, the mechanical steady-state position exhibits clear bistability in the situation of relatively lower phonon number, and it exhibits more controllability as well. This investigation on optical bistability in multi-mode optomechanical systems will have promising applications in optical quantum computing and quantum information processing.