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arXiv · 1806.00544

Direction-Dependent Parity-Time Phase Transition and Non-Reciprocal Directional Amplification with Dynamic Gain-Loss Modulation

Alex Y. Song·Yu Shi·Qian Lin·Shanhui Fan
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Abstract

We show that a dynamic gain-loss modulation in an optical structure can lead to a direction-dependent parity-time (PT) phase transition. The phase transition can be made thresholdless in the forward direction, and yet remains with a non-zero threshold in the backward direction. As a result, non-reciprocal directional amplification can be realized.

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Alex Y. Song, Yu Shi, Qian Lin, Shanhui Fan. 2018-06-01. Direction-Dependent Parity-Time Phase Transition and Non-Reciprocal Directional Amplification with Dynamic Gain-Loss Modulation. https://doi.org/10.1103/physreva.99.013824

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