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arXiv · 1511.08802

Parity-Time Symmetry Breaking in Coupled Nanobeam Cavities

Senlin Zhang·Zhengdong Yong·Yuguang Zhang·Sailing He
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Abstract

The parity-time symmetry (PT symmetry) breaking phenomenon is investigated in a coupled nanobeam cavity system. An exceptional point is observed during the tuning of the relation of the gain/loss and coupling strength of the closely placed nanobeam pairs. The PT symmetry concept can be applied to realize unidirectional light propagation and single mode operation lasers, which may allow for a new way to harness the optical signal in photonic integrated circuits. Otherwise, operating at this particular exceptional point, sensitivity of tiny perturbation detection can be enhanced greatly compared with conventional sensors.

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Senlin Zhang, Zhengdong Yong, Yuguang Zhang, Sailing He. 2015-11-27. Parity-Time Symmetry Breaking in Coupled Nanobeam Cavities. https://arxiv.org/abs/1511.08802

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