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arXiv · 1612.01850

Spectral imaging of topological edge states in plasmonic waveguide arrays

Felix Bleckmann·Zlata Cherpakova·Stefan Linden·Andrea Alberti
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Abstract

We report on the observation of a topologically protected edge state at the interface between two topologically distinct domains of the Su-Schrieffer-Heeger model, which we implement in arrays of evanescently coupled dielectric-loaded surface plasmon polariton waveguides. Direct evidence of the topological character of the edge state is obtained through several independent experiments: Its spatial localization at the interface as well as the restriction to one sublattice is confirmed by real-space leakage radiation microscopy. The corresponding momentum-resolved spectrum obtained by Fourier imaging reveals the midgap position of the edge state as predicted by theory.

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Felix Bleckmann, Zlata Cherpakova, Stefan Linden, Andrea Alberti. 2016-12-06. Spectral imaging of topological edge states in plasmonic waveguide arrays. https://doi.org/10.1103/physrevb.96.045417

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