Coherent control of optical bistability in a microwave-driven V-type atomic system

We demonstrate the optical bistability (OB) behavior of a three-level V-type atomic system inside a unidirectional ring cavity using a microwave field driving a hyperfine transition between two upper excited states. We show that the OB can be controlled by adjusting the intensity of the microwave and coupling driving fields. With the increase of the intensity of the coherent microwave driving field, the bistable threshold intensity increases and the hysteresis loop becomes wider. By contrast, with the increase of the intensity of the coupling field, the bistable threshold intensity decreases and the hysteresis loop becomes narrower. The influences of the relative phase of three fields and the atomic cooperation parameter on the OB behavior are also discussed. Such a system may be used for optimizing and controlling the optical switching process.