Nonreciprocal optical bistability based on Doppler effect in a three-level atomic system

Abstract

We theoretically study nonreciprocal optical bistability in a three-level Λ-type atomic system with the Doppler broadening within a unidirectional ring cavity. The results show that the nonreciprocity optical bistability can be realized by means of the forward or backward probe field propagation. Under the appropriate parameters, the optical isolation ratio and the width of the optical nonreciprocity (ONR) region are sensitive to the probe-detuning, coupling-detuning, coupling-intensity, and the atomic number density. Our work may provide some suggestions for designing nonreciprocal devices such as optical isolators, diodes, and circulators.