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arXiv · 1703.03969

Single-photon nonreciprocal transport in one-dimensional coupled-resonator waveguides

Xun-Wei Xu·Ai-Xi Chen·Yong Li·Yu-xi Liu
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Abstract

We study the transport of a single photon in two coupled one-dimensional semi-infinite coupled-resonator waveguides (CRWs), in which both end sides are coupled to a dissipative cavity. We demonstrate that a single photon can transfer from one semi-infinite CRW to the other nonreciprocally. Based on such nonreciprocity, we further construct a three-port single-photon circulator by a T-shaped waveguide, in which three semi-infinite CRWs are pairwise mutually coupled to each other. The single-photon nonreciprocal transport is induced by the breaking of the time-reversal symmetry and the optimal conditions for these phenomena are obtained analytically. The CRWs with broken time-reversal symmetry will open up a kind of quantum devices with versatile applications in quantum networks.

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Xun-Wei Xu, Ai-Xi Chen, Yong Li, Yu-xi Liu. 2017-03-11. Single-photon nonreciprocal transport in one-dimensional coupled-resonator waveguides. https://doi.org/10.1103/physreva.95.063808

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