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arXiv · 2005.08597

A universal form of arrays with spectral singularities

Dmitry A. Zezyulin·Vladimir V. Konotop
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Abstract

An array of non-Hermitian optical waveguides can operate as a laser or as a coherent perfect absorber, which corresponds to a spectral singularity of the underlying discrete complex potential. We show that all lattice potentials with spectral singularities are characterized by the universal form of the gain-and-loss distribution. Using this result we systematically construct potentials characterized by several spectral singularities at arbitrary wavelengths, as well as potentials with second-order spectral singularities in their spectra. Higher-order spectral singularities demonstrate a greatly enhanced response to incident beams resulting in the excitation of high-intensity lasing modes.

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Dmitry A. Zezyulin, Vladimir V. Konotop. 2020-05-18. A universal form of arrays with spectral singularities. https://doi.org/10.1364/ol.395788

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