▎ 摘　　要

We investigate the dynamic characteristics of a Landau-quantized graphene monolayer system interacting with three infrared laser probe fields in a monodirectional ring cavity, and analyse the input-output properties of the infrared laser probe field under a steady-state condition. The results show that we can effectively control the appearance or disappearance of optical bistability (OB) or optical multistability (OM) by adjusting the relative phase of three coherent fields, the coupling field intensity, as well as the frequency detunings of the probe field and the control field. In addition, we discuss in detail the influences of the left-hand and right-hand circularly polarized component intensity of the control field on the behaviors of OB and OM. Our investigation may be used to build more efficient logic-gate devices to realize an all-optic switching process.