Coupling of QD-based PhC nanocavity with two mechanical modes: an approach to tunable optical switching and sensing applications

Abstract

We theoretically study the dynamical change in the amplification of the output probe field spectra of a hybrid optomechanical system consisting of double mechanical modes coupled to a photonic crystal (PhC) nanocavity. The PhC cavity is also embedded with a quantum dot (QD) (two-level system) and simultaneously driven by an external pump and a probe field. We show that multiple number of transparency windows that appear can be controlled by the QD-cavity coupling strength and also the Fano profiles are directly measured by the resonant frequency of the mechanical mode. We also show the optical transition from bistability to tristability/multistability by adjusting the switching threshold of the system parameters. These results can also be used to study frequency optical nonreciprocity and all-optical switches in multi-resonator photonic devices.