Controllable chaos in the coupled waveguide-optomechanical system with phase shifter

We theoretically investigate chaotic dynamics in an optomechanical system composed of a whispering-gallery-mode (WGM) microresonator and a sensor. We find that tuning the optical phase using a phase shifter and modifying the coupling strength via a unidirectional waveguide (IWG) can induce chaotic motion. The underlying reason for this phenomenon is that adjusting the phase and coupling strength via the phase shifter and IWG bring the system close to an exceptional point (EP), where field localization dynamically enhances the optomechanical nonlinearity, leading to the generation of chaotic motion. In addition, due to the sensitivity of chaos to phase in the vicinity of the EP, we propose a theoretical scheme to measure the optical phase perturbations using chaos. Our work may offer an alternative approach to chaos generation with current experimental technology and provide theoretical guidance for optical signal processing and chaotic secure communication.