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arXiv · 1811.04839

Scattering-free pulse propagation through invisible non-Hermitian disorder

Andre Brandstötter·Konstantinos G. Makris·Stefan Rotter
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Abstract

We demonstrate a new design principle for unidirectionally invisible non-Hermitian structures that are not only invisible for one specific wavelength but rather for a broad frequency range. Our idea is based on the concept of constant-intensity waves, which can propagate even through highly disordered media without back-scattering or intensity variations. Contrary to already existing invisibility studies, our new design principle requires neither a specific symmetry (like $\mathcal{PT}$-symmetry) nor periodicity, and can thus be applied in a much wider context. This generality combined with broadband frequency stability allows a pulse to propagate through a disordered medium as if the medium was entirely uniform.

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Andre Brandstötter, Konstantinos G. Makris, Stefan Rotter. 2018-11-12. Scattering-free pulse propagation through invisible non-Hermitian disorder. https://doi.org/10.1103/physrevb.99.115402

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