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arXiv · 2003.04246

Breaking Anti-$\mathcal{PT}$ Symmetry by Spinning a Resonator

Huilai Zhang·Ran Huang·Sheng-Dian Zhang·Ying Li·Cheng-Wei Qiu·Franco Nori·Hui Jing
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Abstract

Non-Hermitian systems, with symmetric or antisymmetric Hamiltonians under the parity-time ($\mathcal{PT}$) operations, can have entirely real eigenvalues. This fact has led to surprising discoveries such as loss-induced lasing and topological energy transfer. A merit of anti-$\mathcal{PT}$ systems is free of gain, but in recent efforts on making anti-$\mathcal{PT}$ devices, nonlinearity is still required. Here, counterintuitively, we show how to achieve anti-$\mathcal{PT}$ symmetry and its spontaneous breaking in a linear device by spinning a lossy resonator. Compared with a Hermitian spinning device, significantly enhanced optical isolation and ultrasensitive nanoparticle sensing are achievable in the anti-$\mathcal{PT}$-broken phase. In a broader view, our work provides a new tool to study anti-$\mathcal{PT}$ physics, with such a wide range of applications as anti-$\mathcal{PT}$ lasers, anti-$\mathcal{PT}$ gyroscopes, and anti-$\mathcal{PT}$ topological photonics or optomechanics.

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Huilai Zhang, Ran Huang, Sheng-Dian Zhang, Ying Li, Cheng-Wei Qiu, Franco Nori, Hui Jing. 2020-03-09. Breaking Anti-$\mathcal{PT}$ Symmetry by Spinning a Resonator. https://doi.org/10.1021/acs.nanolett.0c03119

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