▎ 摘　　要

In this paper, the low-threshold optical bistability (OB) of a reflected light beam at teraheritz frequencies is achieved by using a multilayer structure where monolayer graphene is coated on one-dimensional photonic crystal (1D PC) separated by a top layer. This low-threshold OB phenomenon originates from the enhancement of the electrical field owing to the excitation of optical Tamm states (OTSs) at the interface between the graphene and ID PC. It is found that the hysterical behavior of the reflected light can be electrically controlled by properly varying the applied voltage on the graphene. Moreover, the bistable behavior of the proposed structure is proved sensitive to incidence angle and the dispersion characteristics of the top layer, thus making this configuration a prime candidate for future experimental investigation at the terahertz range. (C) 2018 Optical Society of America under the terms of the OSA Open Access Publishing Agreement