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Abstract The rise of quantum science and technologies motivates photonics research to seek new platforms with strong light-matter interactions to facilitate quantum behaviors at moderate light intensities. Topological polaritons (TPs) offer an ideal platform in this context, with unique properties stemming from resilient topological states of light strongly coupled with matter. Here we explore polaritonic metasurfaces based on 2D transition metal dichalcogenides (TMDs) as a promising platform for topological polaritonics. We show that the strong coupling between topological photonic modes of the metasurface and excitons in TMDs yields a topological polaritonic Z2phase. We experimentally confirm the emergence of one-way spin-polarized edge TPs in metasurfaces integrating MoSe2and WSe2. Combined with the valley polarization in TMD monolayers, the proposed system enables an approach to engage the photonic angular momentum and valley and spin of excitons, offering a promising platform for photonic/solid-state interfaces for valleytronics and spintronics.
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Topological metasurfaces [Invited]
Topological photonics allows for the deterministic creation of electromagnetic modes of any dimensionality lesser than that of the system. In the context of two-dimensional systems such as metasurfaces, topological photonics enables trapping of light in 0D cavities defined by boundaries of higher-order topological insulators and topological defects, as well as guiding of optical fields along 1D boundaries between topologically distinct domains. More importantly, it allows engineering interactions of topological modes with radiative continuum, which opens new opportunities to control light-matter interactions, scattering, generation, and emission of light. This review article aims at highlighting recent work in the field focusing on the control of radiation and generation of light in topological metasurfaces.
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- PAR ID:
- 10527819
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Optical Materials Express
- Volume:
- 14
- Issue:
- 8
- ISSN:
- 2159-3930
- Format(s):
- Medium: X Size: Article No. 2065
- Size(s):
- Article No. 2065
- Sponsoring Org:
- National Science Foundation
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