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arXiv · 1001.0962

Spectral singularities and Bragg scattering in complex crystals

S. Longhi
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Abstract

Spectral singularities that spoil the completeness of Bloch-Floquet states may occur in non-Hermitian Hamiltonians with complex periodic potentials. Here an equivalence is established between spectral singularities in complex crystals and secularities that arise in Bragg diffraction patterns. Signatures of spectral singularities in a scattering process with wave packets are elucidated for a PT-symmetric complex crystal.

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S. Longhi. 2010-01-06. Spectral singularities and Bragg scattering in complex crystals. https://doi.org/10.1103/physreva.81.022102

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