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arXiv · 2405.15612

Dual opposing quadrature-PT symmetry

Wencong Wang·Jacob Kokinda·Jiazhen Li·Qing Gu·Dongmei Liu·Jianming Wen
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Abstract

Our recent research on type-I quadrature parity-time (PT) symmetry, utilizing an open twin-beam system, not only enables observing genuine quantum photonic PT symmetry amid phase-sensitive amplification (PSA) and loss in the presence of Langevin noise but also reveals additional classical-to-quantum (C2Q) transitions in quadrature and relative-intensity noise fluctuations. In contrast to the previous setup, our exploration of an alternative system assuming no loss involves a type-II PSA-only scheme. This scheme facilitates dual opposing quadrature PT symmetry, offering a comprehensive and complementary comprehension of C2Q transitions and anti-Hermiticity-enhanced quantum sensing. Furthermore, our investigation into the correlation with the Einstein-Podolsky-Rosen criteria uncovers previously unexplored connections between PT symmetry and nonclassicality, as well as quantum entanglement within the continuous-variable framework.

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Wencong Wang, Jacob Kokinda, Jiazhen Li, Qing Gu, Dongmei Liu, Jianming Wen. 2024-05-24. Dual opposing quadrature-PT symmetry. https://doi.org/10.1016/j.isci.2024.111655

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