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arXiv · 1907.03294

Synthetic parity-time symmetry breaking in a single microcavity

Fangxing Zhang·Yaming Feng·Li Ge·Wenjie Wan
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Abstract

Non-Hermitian systems based on parity-time (PT) symmetry reveal rich physics beyond the Hermitian regime. So far, realizations of PT-symmetric systems have been limited to the spatial domain. Here we theoretically and experimentally demonstrate PT symmetry in a synthetic spectral dimension induced by nonlinear Brillouin scattering in a single optical microcavity, where electromagnetically induced transparency or absorption in two spectral resonances provides the optical gain and loss to observe a phase transition between two symmetry regimes. This scheme provides a new paradigm towards the investigation of non-Hermitian physics in a synthetic photonic dimension for all-optical signal processing and quantum information science.

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Fangxing Zhang, Yaming Feng, Li Ge, Wenjie Wan. 2019-07-07. Synthetic parity-time symmetry breaking in a single microcavity. https://doi.org/10.1103/physrevlett.124.053901

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