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arXiv · 1901.06805

Anti-Parity-Time Symmetric Optical Four-Wave Mixing in Cold Atoms

Yue Jiang·Yefeng Mei·Ying Zuo·Yanhua Zhai·Jensen Li·Jianming Wen·Shengwang Du
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Abstract

Non-Hermitian optical systems with parity-time (PT) symmetry have recently revealed many intriguing prospects that outperform conservative structures. The prevous works are mostly rooted in complex arrangements with controlled gain-loss interplay. Here, we demonstrate anti-PT symmetry inherent in nonlinear optical interactions based upon forward optical four-wave mixing in a laser-cooled atomic ensemble with negligible linear gain and loss. We observe the pair of frequency modes undergo a nontrivial anti-PT phase transition between coherent power oscillation and optical parametric amplification in presence of a large phase mismatch.

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Yue Jiang, Yefeng Mei, Ying Zuo, Yanhua Zhai, Jensen Li, Jianming Wen, Shengwang Du. 2019-07-31. Anti-Parity-Time Symmetric Optical Four-Wave Mixing in Cold Atoms. https://doi.org/10.1103/physrevlett.123.193604

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