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The generation of exciton–polaritons through strong light–matter interactions represents an emerging platform for exploring quantum phenomena. A significant challenge in colloidal nanocrystal-based polaritonic systems is the ability to operate at room temperature with high fidelity. Here, we demonstrate the generation of room-temperature exciton–polaritons through the coupling of CdSe nanoplatelets (NPLs) with a Fabry–Pérot optical cavity, leading to a Rabi splitting of 74.6 meV. Quantum–classical calculations accurately predict the complex dynamics between the many dark state excitons and the optically allowed polariton states, including the experimentally observed lower polariton photoluminescence emission, and the concentration of photoluminescence intensities at higher in-plane momenta as the cavity becomes more negatively detuned. The Rabi splitting measured at 5 K is similar to that at 300 K, validating the feasibility of the temperature-independent operation of this polaritonic system. Overall, these results show that CdSe NPLs are an excellent material to facilitate the development of room-temperature quantum technologies.
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Strong coupling of polaritons at room temperature in a GaAs/AlGaAs structure
We report direct measurement of the dispersion relation of polaritons in GaAs/AlGaAs microcavity structures at room temperature, which clearly shows that the polaritons are in the strong-coupling limit. The Rabi splitting ranges from 12.3 to 15.2 meV depending on the detuning, significantly exceeding the heavy-hole exciton half width of 5.2 meV. As the polariton density increases, the Rabi splitting decreases; but even when the polariton gas becomes a coherent, Bose-condensate-like state, the polaritons retain a strong exciton component, as seen in the nonlinear energy shift of the light emission. This opens up the possibility of polaritonic devices at room temperature in a material system which can be grown with very high quality and uniformity.
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- Award ID(s):
- 2306977
- PAR ID:
- 10660866
- Publisher / Repository:
- APS
- Date Published:
- Journal Name:
- Physical Review B
- Volume:
- 112
- Issue:
- 4
- ISSN:
- 2469-9950
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript
- Journal Article:
- https://doi.org/10.1103/dstp-cbcf
