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arXiv · 2303.00189

Quantum PT-Phase Diagram in a Non-Hermitian Photonic Structure

Xinchen Zhang·Yun Ma·Qi Liu·Nuo Wang·Yali Jia·Qi Zhang·Zhanqiang Bai·Junxiang Zhang·Qihuang Gong·Ying Gu
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Abstract

Photonic structures have an inherent advantage to realize PT-phase transition through modulating the refractive index or gain-loss. However, quantum PT properties of these photonic systems have not been comprehensively studied yet. Here, in a bi-photonic structure with loss and gain simultaneously existing, we analytically obtained the quantum PT-phase diagram under the steady state condition. To characterize the PT-symmetry or -broken phase, we define an Hermitian exchange operator expressing the exchange between quadrature variables of two modes. If inputting several-photon Fock states into a PT-broken bi-waveguide splitting system, most photons will concentrate in the dominant waveguide with some state distributions. Quantum PT-phase diagram paves the way to the quantum state engineering, quantum interferences, and logic operations in non-Hermitian photonic systems.

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Xinchen Zhang, Yun Ma, Qi Liu, Nuo Wang, Yali Jia, Qi Zhang, Zhanqiang Bai, Junxiang Zhang, Qihuang Gong, Ying Gu. 2023-03-01. Quantum PT-Phase Diagram in a Non-Hermitian Photonic Structure. https://arxiv.org/abs/2303.00189

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