Ultralow Threshold Room Temperature Polariton Condensation in Colloidal CdSe/CdS Core/Shell Nanoplatelets

Hongyu Yang; Lei Zhang; Wenbin Xiang; Changgui Lu; Yiping Cui; Jiayu Zhang

doi:10.1002/advs.202200395

Ultralow Threshold Room Temperature Polariton Condensation in Colloidal CdSe/CdS Core/Shell Nanoplatelets

Adv Sci (Weinh). 2022 Jun;9(18):e2200395. doi: 10.1002/advs.202200395. Epub 2022 Apr 24.

Authors

Hongyu Yang¹, Lei Zhang^{1

2}, Wenbin Xiang¹, Changgui Lu¹, Yiping Cui¹, Jiayu Zhang¹

Affiliations

¹ Advanced Photonics Center, Southeast University, Nanjing, Jiangsu, 210096, P. R. China.
² School of Sciences, Nantong University, Nantong, 226019, P. R. China.

Abstract

Room-temperature exciton-polariton Bose-Einstein condensation (BEC), a phase transition to single quantum state with strong nonlinearity, provides a new strategy for coherent light sources and ultralow threshold optic switches. In this work, colloidal CdSe/CdS 2D nanoplatelets are embedded into a microcavity, and exciton-polariton BEC is realized with an ultralow threshold of 0.5 µJ cm^-2 at room temperature. The superlinear power-dependent emission, macroscopic occupation of the ground state, strong blueshift and broadening of the emission peak, and long-range coherence strongly confirm the realization of the polariton laser. This work suggests considerable prospects for colloidal nanoplatelets in low-cost, high-performance polariton devices, and coherent light sources.

Keywords: coherent light source; colloidal nanoplatelets; polariton BEC; strong exciton-photon coupling.

Abstract

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