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Anomalous Light Scattering by Topological PT-symmetric Particle Arrays.

ABSTRACT: Robust topological edge modes may evolve into complex-frequency modes when a physical system becomes non-Hermitian. We show that, while having negligible forward optical extinction cross section, a conjugate pair of such complex topological edge modes in a non-Hermitian -symmetric system can give rise to an anomalous sideway scattering when they are simultaneously excited by a plane wave. We propose a realization of such scattering state in a linear array of subwavelength resonators coated with gain media. The prediction is based on an analytical two-band model and verified by rigorous numerical simulation using multiple-multipole scattering theory. The result suggests an extreme situation where leakage of classical information is unnoticeable to the transmitter and the receiver when such a -symmetric unit is inserted into the communication channel.

SUBMITTER: Ling CW

PROVIDER: S-EPMC5131320 | biostudies-literature | 2016 Dec

REPOSITORIES: biostudies-literature

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Anomalous Light Scattering by Topological PT-symmetric Particle Arrays.

Ling C W CW Choi Ka Hei KH Mok T C TC Zhang Zhao-Qing ZQ Fung Kin Hung KH

Scientific reports 20161201

Robust topological edge modes may evolve into complex-frequency modes when a physical system becomes non-Hermitian. We show that, while having negligible forward optical extinction cross section, a conjugate pair of such complex topological edge modes in a non-Hermitian -symmetric system can give rise to an anomalous sideway scattering when they are simultaneously excited by a plane wave. We propose a realization of such scattering state in a linear array of subwavelength resonators coated with ...[more]

PMID: 27905504

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