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arXiv · 1908.07210

Experimental demonstration of Cavity-Free Optical Isolators and Optical Circulators

En-Ze Li·Dong-Sheng Ding·Yi-Chen Yu·Ming-Xin Dong·Lei Zeng·Wei-Hang Zhang·Ying-Hao Ye·Huai-Zhi Wu·Zhi-Han Zhu·Wei Gao·Guang-Can Guo·Bao-Sen Shi
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Abstract

Cavity-free optical nonreciprocity components, which have an inherent strong asymmetric interaction between the forward- and backward-propagation direction of the probe field, are key to produce such as optical isolators and circulators. According to the proposal presented by Xia et al., [Phys. Rev. Lett. 121, 203602 (2018)], we experimentally build a device that uses cross-Kerr nonlinearity to achieve a cavity-free optical isolator and circulator. Its nonreciprocal behavior arises from the thermal motion of N-type configuration atoms, which induces a strong chiral cross-Kerr nonlinear response for the weak probe beam. We obtain a two-port optical isolator for up to 20 dB of isolation ratio in a specially designed Sagnac interferometer. The distinct propagation directions of the weak probe field determine its cross-phase shift and transmission, by which we demonstrate the accessibility of a four-port optical circulator.

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En-Ze Li, Dong-Sheng Ding, Yi-Chen Yu, Ming-Xin Dong, Lei Zeng, Wei-Hang Zhang, Ying-Hao Ye, Huai-Zhi Wu, Zhi-Han Zhu, Wei Gao, Guang-Can Guo, Bao-Sen Shi. 2019-08-20. Experimental demonstration of Cavity-Free Optical Isolators and Optical Circulators. https://doi.org/10.1103/physrevresearch.2.033517

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