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arXiv · 1909.11113

Topological Spaser

Jhih-Sheng Wu·Vadym Apalkov·Mark I. Stockman
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Abstract

We theoretically introduce a topological spaser, which consists of a hexagonal array of plasmonic metal nanoshells containing an achiral gain medium in their cores. Such a spaser can generate two mutually time-reversed chiral surface plasmon modes in the $\mathbf K$- and $\mathbf K^\prime$-valleys, which carry the opposite topological charges, $\pm1$, and are described by a two-dimensional $E^{\prime}$ representation of the $D_{3h}$ point symmetry group. Due to the mode competition, this spaser exhibits a bistability: only one of these two modes generates, which is a spontaneous symmetry breaking. Such a spaser can be used for an ultrafast all-optical memory and information processing

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Jhih-Sheng Wu, Vadym Apalkov, Mark I. Stockman. 2019-10-04. Topological Spaser. https://doi.org/10.1103/physrevlett.124.017701

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