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arXiv · 2003.11151

Anti-Parity-Time Symmetry in Passive Nanophotonics

Heng Fan·Jiayang Chen·Zitong Zhao·Jianming Wen·Yuping Huang
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Abstract

Parity-time (PT) symmetry in non-Hermitian optical systems promises distinct optical effects and applications not found in conservative optics. Its counterpart, anti-PT symmetry, subscribes another class of intriguing optical phenomena and implies complementary techniques for exotic light manipulation. Despite exciting progress, so far anti-PT symmetry has only been realized in bulky systems or with optical gain. Here, we report an on-chip realization of non-Hermitian optics with anti-PT symmetry, by using a fully-passive, nanophotonic platform consisting of three evanescently coupled waveguides. By depositing a metal film on the center waveguide to introduce strong loss, an anti-PT system is realized. Using microheaters to tune the waveguides' refractive indices, striking behaviors are observed such as equal power splitting, synchronized amplitude modulation, phase-controlled dissipation, and transition from anti-PT symmetry to its broken phase. Our results highlight exotic anti-Hermitian nanophotonics to be consolidated with conventional circuits on the same chip, whereby valuable chip devices can be created for quantum optics studies and scalable information processing.

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Heng Fan, Jiayang Chen, Zitong Zhao, Jianming Wen, Yuping Huang. 2020-03-24. Anti-Parity-Time Symmetry in Passive Nanophotonics. https://arxiv.org/abs/2003.11151

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