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arXiv · 1710.04879

Plasmon-exciton polaritons in 2D semiconductor/metal interfaces

Abstract

The realization and control of polaritons is of paramount importance in the prospect of novel photonic devices. Here, we investigate the emergence of plasmon-exciton polaritons in hybrid structures consisting of a two-dimensional (2D) transition metal dichalcogenide (TMDC) deposited onto a metal substrate or coating a metallic thin-film. We determine the polaritonic spectrum and show that, in the former case, the addition of a top dielectric layer, and, in the latter, the thickness of the metal film,can be used to tune and promote plasmon-exciton interactions well within the strong coupling regime. Our results demonstrate that Rabi splittings exceeding 100 meV can be readily achieved in planar dielectric/TMDC/metal structures under ambient conditions. We thus believe that this work provides a simple and intuitive picture to tailor strong coupling in plexcitonics, with potential applications for engineering compact photonic devices with tunable optical properties.

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BibTeXRIS

P. A. D. Gonçalves, L. P. Bertelsen, Sanshui Xiao, N. Asger Mortensen. 2017-12-13. Plasmon-exciton polaritons in 2D semiconductor/metal interfaces. https://doi.org/10.1103/physrevb.97.041402

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