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arXiv · 1612.04628

Floquet control of the gain and loss in a PT-symmetric optical coupler

Yi Wu·Bo Zhu·Shufang Hu·Zheng Zhou·Honghua Zhong
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Abstract

Controlling the balanced gain and loss in a PT-symmetric system is a rather challenging task. Utilizing Floquet theory, we explore the constructive role of periodic modulation in controlling the gain and loss of a PT-symmetric optical coupler. It is found that the gain and loss of the system can be manipulated by applying a periodic modulation. Further, such an original non-Hermitian system can even be modulated into an effective Hermitian system derived by the high-frequency Floquet method. Therefore, compared with other PT symmetry control schemes, our protocol can modulate the unbroken PT-symmetric range to a wider parameter region. Our results provide a promising approach for controlling the gain and loss of a realistic system.

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Yi Wu, Bo Zhu, Shufang Hu, Zheng Zhou, Honghua Zhong. 2016-12-14. Floquet control of the gain and loss in a PT-symmetric optical coupler. https://arxiv.org/abs/1612.04628

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