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arXiv · 1008.5306

Invisibility in non-Hermitian tight-binding lattices

Stefano Longhi
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Abstract

Reflectionless defects in Hermitian tight-binding lattices, synthesized by the intertwining operator technique of supersymmetric quantum mechanics, are generally not invisible and time-of-flight measurements could reveal the existence of the defects. Here it is shown that, in a certain class of non-Hermitian tight-binding lattices with complex hopping amplitudes, defects in the lattice can appear fully invisible to an outside observer. The synthesized non-Hermitian lattices with invisible defects possess a real-valued energy spectrum, however they lack of parity-time (PT) symmetry, which does not play any role in the present work.

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Stefano Longhi. 2010-08-31. Invisibility in non-Hermitian tight-binding lattices. https://doi.org/10.1103/physreva.82.032111

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