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arXiv · 1306.0667

Invisible defects in complex crystals

S. Longhi·G. Della Valle
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Abstract

We show that invisible localized defects, i.e. defects that can not be detected by an outside observer, can be realized in a crystal with an engineered imaginary potential at the defect site. The invisible defects are synthesized by means of supersymmetric (Darboux) transformations of an ordinary crystal using band-edge wave functions to construct the superpotential. The complex crystal has an entire real-valued energy spectrum and Bragg scattering is not influenced by the defects. An example of complex crystal synthesis is presented for the Mathieu potential.

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S. Longhi, G. Della Valle. 2013-06-04. Invisible defects in complex crystals. https://doi.org/10.1016/j.aop.2013.03.011

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