Diffraction-free beam propagation at the exceptional point of non-Hermitian Glauber Fock lattices

Cem Yuce; Hamidreza Ramezani

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arXiv · 2009.12880

Diffraction-free beam propagation at the exceptional point of non-Hermitian Glauber Fock lattices

Cem Yuce·Hamidreza Ramezani

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Abstract

We construct localized beams that are located at the edge of a non-Hermitian Glauber Fock (NGF) lattice made of coupled waveguides and can propagate for a long distance without almost no diffraction. Specifically, we calculate the closed-form of the eigenstates at the exceptional point of a semi-infinite NGF lattice composed of waveguides which are coupled in a unidirectional manner. We use the closed-form solution to construct the non-diffracting beams in finite NGF lattices. We provide a numerical approach to find other lattices that are capable of supporting non-diffracting beams at an exceptional point.

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Cem Yuce, Hamidreza Ramezani. 2020-09-27. Diffraction-free beam propagation at the exceptional point of non-Hermitian Glauber Fock lattices. https://arxiv.org/abs/2009.12880

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