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.
- Award ID(s):
- 1719875
- NSF-PAR ID:
- 10325375
- Date Published:
- Journal Name:
- Science Advances
- Volume:
- 7
- Issue:
- 19
- ISSN:
- 2375-2548
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract Room temperature stable excitons in layered two‐dimensional (2D) transition metal dichalcogenides (TMDs) offer a unique route for engineering light and matter interactions. Due to the strong optical dispersion near the excitonic transitions, a high refractive index arises in these ultrathin semiconductors.[1,2]Utilizing this behavior, strongly confined Fano type optical resonances in an ultrathin (i.e., ≈12 nm) tungsten disulfide (WS2) photonic crystal (PhC) directly fabricated on a TMD‐on‐glass platform are reported. In this approach, Fano‐type WS2photonic resonances strongly couple to the WS2excitonic dispersion engender self‐resonant exciton‐polaritons with an out‐of‐plane optical confinement exceeding that provided by surface plasmon polaritons in the visible. The large spatial light‐matter overlap endowed by this unique monolithic self‐coupling scheme is utilized for steering of enhanced 2D WSe2excitonic photoluminescence in a truly TMD integrated system. It is envisioned that the strong light matter interaction on the TMD‐on‐glass platform will unfold the prospects of ultrathin exciton‐polaritonic resonators.
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1126/sciadv.abe8087
