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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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Tunable topological phase transition in the telecommunication wavelength
Recent progress in the Valley Hall insulator has demonstrated a nontrivial topology property due to the distinct valley index in 2D semiconductor systems. In this work, we propose a highly tunable topological phase transition based on valley photonic crystals. The topological phase transition is realized by the inversion symmetry broken due to the refractive index change of structures consisting of optical phase change material (OPCM) with thermal excitation of different sites in a honeycomb lattice structure. Besides, simulations of light propagation at sharp corners and pseudo-spin photon coupling are conducted to quantitatively examine the topological protection. Compared with other electro-optical materials based on reconfigurable topological photonics, a wider bandwidth and greater tunability of both central bandgap frequency and topological phase transition can happen in the proposed scheme. Our platform has great potential in practical applications in lasing, light sensing, and high-contrast tunable optical filters.
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- Award ID(s):
- 1907423
- PAR ID:
- 10412136
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Optical Materials Express
- Volume:
- 13
- Issue:
- 6
- ISSN:
- 2159-3930
- Format(s):
- Medium: X Size: Article No. 1571
- Size(s):
- Article No. 1571
- Sponsoring Org:
- National Science Foundation
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