Controllable optical bistability in a Fabry–Pérot cavity with a nonlinear three-dimensional Dirac semimetal

Abstract

Optical bistability (OB), capable of rapidly and reversibly transforming a parameter of an optical signal from one state to another, and the homologous nonlinear optical bistable devices are core components to realize high-speed all-optical communications and all-optical networks. In this paper, we theoretically investigated the controllable OB from a Fabry-Perot (FP) cavity with nonlinear three-dimensional Dirac semimetal (3D DSM) in the terahertz band. OB stems from the third-order nonlinear bulk conductivity of 3D DSM and the resonance mode has a positive effect on the generation of OB. This FP cavity structure achieves the tunability of OB due to that the transmittance and the reflectance could be modulated by the Fermi energy of 3D DSM. We believe this FP cavity configuration could provide a reference idea for realizing tunable bistable device.