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arXiv · 1604.04025

Observation of Parity-Time Symmetry in Optically Induced Atomic Lattices

Zhaoyang Zhang·Yiqi Zhang·Jiteng Sheng·Liu Yang·Mohammad-Ali Miri·Demetrios N. Christodoulides·Bing He·Yanpeng Zhang·Min Xiao
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Abstract

We experimentally demonstrate PT-symmetric optical lattices with periodical gain and loss profiles in a coherently-prepared four-level N-type atomic system. By appropriately tuning the pertinent atomic parameters, the onset of PT-symmetry breaking is observed through measuring an abrupt phase-shift jump between adjacent gain and loss waveguides. The experimental realization of such readily reconfigurable and effectively controllable PT-symmetric waveguide array structure sets a new stage for further exploiting and better understanding the peculiar physical properties of these non-Hermitian systems in atomic settings.

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Zhaoyang Zhang, Yiqi Zhang, Jiteng Sheng, Liu Yang, Mohammad-Ali Miri, Demetrios N. Christodoulides, Bing He, Yanpeng Zhang, Min Xiao. 2016-11-28. Observation of Parity-Time Symmetry in Optically Induced Atomic Lattices. https://doi.org/10.1103/physrevlett.117.123601

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