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Abstract A growing number of organic materials have recently been reported to achieve room‐temperature exciton‐polariton (polariton) condensation, which is an essential requirement for practical polaritonic applications. Notably, fluorescent dyes utilizing the small‐molecule, ionic isolation lattice (SMILES) method have solved the long‐standing challenges of conventional organic dyes and have been successfully implemented in cavities to realize condensation. However, almost all demonstrations of molecular polariton condensates have inherently large spectral linewidth and poor temporal coherence arising from intrinsic disorder and low quality (Q) factor of the cavity. Here, exciton‐polaritons are realised using fluorescent dye SMILES in a high Q factor microcavity and we observe polariton condensates with a linewidth of 175 µeV. These polariton condensates exhibit temporal coherence of 30.3 ± 8.0 ps, indicating the highly coherent nature of the narrow linewidth condensates. These results set the stage for realizing highly coherent and robust polaritonic devices operating at room temperature.
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Trapping-induced quantum beats in a van-der-Waals heterostructure microcavity observed by two-dimensional micro-spectroscopy
Spatial confinement has been frequently engineered to control the flow and relaxation dynamics of exciton polaritons. While widely investigated in GaAs microcavities, exciton-polariton coupling between discretized polariton modes arising from spatially confined 2D crystals been has been less exhaustively studied. Here, we use coherent 2D photoluminescence-detected micro-spectroscopy to detect oscillating 2D peaks exclusively from a spatial trap in a microcavity with an embedded van-der-Waals heterostructure at room temperature. We observe a wide variation of oscillatory phases as a function of spectral position within the 2D spectrum, which suggests the existence of a coupling between the discretized polariton modes. The latter is accompanied by the generation of coherent phonons.
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- PAR ID:
- 10462704
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Optical Materials Express
- Volume:
- 13
- Issue:
- 10
- ISSN:
- 2159-3930
- Format(s):
- Medium: X Size: Article No. 2798
- Size(s):
- Article No. 2798
- Sponsoring Org:
- National Science Foundation
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