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

We construct localized beams in a non-Hermitian Glauber Fock (NGF) lattice of coupled waveguides and show that they can propagate over a long distance withalmost no diffraction. We specifically obtain the diffraction-free beams in a finite NGF lattice at the exceptional point (EP) by using the exact eigenstates of the semi-infinite unidirectional NGF lattice. We provide a numerical approach to finding other lattices that are capable of supporting non-diffracting beams at EPs.

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IOP Science
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Journal Name:
Journal of Optics
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Medium: X
Sponsoring Org:
National Science Foundation
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