Non-Hermitian control of localization in mosaic photonic lattices

Stefano Longhi

doi:10.1063/5.0175675

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arXiv · 2310.02334

Non-Hermitian control of localization in mosaic photonic lattices

Stefano Longhi

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Abstract

Exploring the deep insights into localization, disorder, and wave transport in non-Hermitian systems is an emergent area of research of relevance in different areas of physics. Engineered photonic lattices, with spatial regions of optical gain and loss, provide a prime and simple physical platform for tailoring non-Hermitian Hamiltonians and for unveiling the intriguing interplay between disorder and non-Hermiticity. Here it is shown that in mosaic photonic lattices with on-site uncorrelated disorder or quasi-periodic order, the addition of uniform loss at alternating sites of the lattice results in the suppression or enhancement of wave spreading, thus providing a simple method for non-Hermitian control of wave transport in disordered systems. The results are illustrated by considering discrete-time quantum walks in synthetic photonic lattices.

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physics.optics cond-mat.dis-nn quant-ph

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Stefano Longhi. 2023-10-03. Non-Hermitian control of localization in mosaic photonic lattices. https://doi.org/10.1063/5.0175675

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