Nonreciprocity via Nonlinearity and Synthetic Magnetism
Xun-Wei Xu, Yong Li, Baijun Li, Hui Jing, Ai-Xi Chen
Abstract
We propose how to realize nonreciprocity for a weak input optical field via nonlinearity and synthetic magnetism. We show that the photons transmitted from a linear cavity to a nonlinear cavity (i.e., a linear-nonlinear optical molecule) exhibit nonreciprocal photon blockade but no clear nonreciprocal transmission. Both nonreciprocal transmission and nonreciprocal photon blockade can be observed, when one or two auxiliary modes are coupled to the linear-nonlinear optical molecule to generate an artificial magnetic field. A similar method can be used to create and manipulate nonreciprocal transmission and nonreciprocal photon blockade for photons bidirectionally transport in a nonlinear-nonlinear optical molecule. Additionally, a photon circulator with nonreciprocal photon blockade is designed in cyclic three-nonlinear-mode system. The combination of nonlinearity and synthetic magnetism provides us an effective way towards the realization of quantum nonreciprocal devices, e.g., nonreciprocal single-photon sources and single-photon diodes.