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arXiv · 1908.08323

Nonreciprocal transition between two nondegenerate energy levels

Xun-Wei Xu·Yan-Jun Zhao·Hui Wang·Ai-Xi Chen·Yu-xi Liu
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Abstract

Stimulated emission and absorption are two fundamental processes of light-matter interaction, and the coefficients of the two processes should be equal in general. However, we will describe a generic method to realize significant difference between the stimulated emission and absorption coefficients of two nondegenerate energy levels, which we refer to as nonreciprocal transition. As a simple implementation, a cyclic three-level atom system, comprising two nondegenerate energy levels and one auxiliary energy level, is employed to show nonreciprocal transition via a combination of synthetic magnetism and reservoir engineering. Moreover, a single-photon nonreciprocal transporter is proposed using two one dimensional semi-infinite coupled-resonator waveguides connected by an atom with nonreciprocal transition effect. Our work opens up a route to design atom-mediated nonreciprocal devices in a wide range of physical systems.

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Xun-Wei Xu, Yan-Jun Zhao, Hui Wang, Ai-Xi Chen, Yu-xi Liu. 2019-08-22. Nonreciprocal transition between two nondegenerate energy levels. https://doi.org/10.1364/prj.412904

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