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arXiv · 2107.10421

Topological optomechanical amplifier with synthetic $\mathcal{PT}$-symmetry

Jian-Qi Zhang·Jing-Xin Liu·Hui-Lai Zhang·Zhi-Rui Gong·Shuo Zhang·Lei-Lei Yan·Shi-Lei Su·Hui Jing·Mang Feng
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Abstract

We propose how to achieve synthetic $\mathcal{PT}$ symmetry in optomechanics without using any active medium. We find that harnessing the Stokes process in such a system can lead to the emergence of exceptional point (EP), i.e., the coalescing of both the eigenvalues and the eigenvectors of the system. By encircling the EP, both non-reciprocal optical amplification and chiral mode switching can be achieved. As a result, our synthetic $\mathcal{PT}$-symmetric optomechanics works as a topological optomechanical amplifier. This provides a surprisingly simplified route to realize $\mathcal{PT}$-symmetric optomechanics, indicating that a wide range of EP devices can be created and utilized for various applications such as topological optical engineering and nanomechanical processing or sensing.

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Jian-Qi Zhang, Jing-Xin Liu, Hui-Lai Zhang, Zhi-Rui Gong, Shuo Zhang, Lei-Lei Yan, Shi-Lei Su, Hui Jing, Mang Feng. 2021-07-22. Topological optomechanical amplifier with synthetic $\mathcal{PT}$-symmetry. https://doi.org/10.1515/nanoph-2021-0721

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