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arXiv · 2303.00809

Topological edge states in equidistant arrays of Lithium Niobate nano-waveguides

Andrey V. Gorbach·Jesper Beer·Anton Souslov
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Abstract

We report that equidistant 1D arrays of thin-film Lithium Niobate nano-waveguides generically support topological edge states. Unlike conventional coupled-waveguide topological systems, the topological properties of these arrays are dictated by the interplay between intra- and inter-modal couplings of two families of guided modes with different parities. Exploiting two modes within the same waveguide to design a topological invariant allows us to decrease the system size by a factor of two and substantially simplify the structure. We present two example geometries where topological edge states of different types (based on either quasi-TE or quasi-TM modes) can be observed within a wide range of wavelengths and array spacings.

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Andrey V. Gorbach, Jesper Beer, Anton Souslov. 2023-03-01. Topological edge states in equidistant arrays of Lithium Niobate nano-waveguides. https://doi.org/10.1364/ol.485415

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