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arXiv · 1202.5629

Wave scattering on a domain wall in a chain of PT-symmetric couplers

Sergey V. Suchkov·Sergey V. Dmitriev·Boris A. Malomed·Yuri S. Kivshar
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Abstract

We study wave propagation in linear arrays composed of pairs of conjugate waveguides with balanced gain and loss, i.e. arrays of the PT-symmetric couplers, where the linear spectrum is known to feature high-frequency and low-frequency branches. We introduce a domain wall by switching the gain and loss in a half of the array, and analyze the scattering of linear waves on this defect. The analysis reveals two major effects: amplification of both reflected and transmitted waves, and excitation of the reflected and transmitted low-frequency and high-frequency waves by the incident high-frequency and low-frequency waves, respectively.

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Sergey V. Suchkov, Sergey V. Dmitriev, Boris A. Malomed, Yuri S. Kivshar. 2012-02-25. Wave scattering on a domain wall in a chain of PT-symmetric couplers. https://doi.org/10.1103/physreva.85.033825

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