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arXiv · 1307.2695

PT Symmetry via Electromagnetically Induced Transparency

Huijun Li·Jianpeng Dou·Guoxiang Huang
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Abstract

We propose a scheme to realize parity-time (PT) symmetry via electromagnetically induced transparency (EIT). The system we consider is an ensemble of cold four-level atoms with an EIT core. We show that the cross-phase modulation contributed by an assisted field, the optical lattice potential provided by a far-detuned laser field, and the optical gain resulted from an incoherent pumping can be used to construct a PT-symmetric complex optical potential for probe field propagation in a controllable way. Comparing with previous study, the present scheme uses only a single atomic species and hence is easy for the physical realization of PT-symmetric Hamiltonian via atomic coherence.

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Huijun Li, Jianpeng Dou, Guoxiang Huang. 2013-07-10. PT Symmetry via Electromagnetically Induced Transparency. https://doi.org/10.1364/oe.21.032053

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