Role of the Exciton-Polariton in a Continuous-Wave Optically Pumped CsPbBr3 Perovskite Laser

Qiuyu Shang; Meili Li; Liyun Zhao; Dingwei Chen; Shuai Zhang; Shulin Chen; Peng Gao; Chao Shen; Jun Xing; Guichuan Xing; Bo Shen; Xinfeng Liu; Qing Zhang

doi:10.1021/acs.nanolett.0c02462

Role of the Exciton-Polariton in a Continuous-Wave Optically Pumped CsPbBr₃ Perovskite Laser

Nano Lett. 2020 Sep 9;20(9):6636-6643. doi: 10.1021/acs.nanolett.0c02462. Epub 2020 Aug 19.

Authors

Qiuyu Shang¹, Meili Li¹, Liyun Zhao¹, Dingwei Chen², Shuai Zhang³, Shulin Chen^{4

5}, Peng Gao^{4

5}, Chao Shen², Jun Xing⁶, Guichuan Xing⁷, Bo Shen^{4

8}, Xinfeng Liu³, Qing Zhang^{1

8}

Affiliations

¹ Department of Materials Science and Engineering, College of Engineering, Peking University, Beijing 100871, China.
² State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China.
³ CAS Key Laboratory of Standardization and Measurement for Nanotechnology, CAS Center of Excellence for Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, China.
⁴ School of Physics, Peking University, Beijing 100871, China.
⁵ Electron Microscopy Laboratory, International Center for Quantum Materials, School of Physics, Peking University, Beijing 100871, China.
⁶ Key Laboratory of Eco-Chemical Engineering, Ministry of Education, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, China.
⁷ Joint Key Laboratory of the Ministry of Education, Institute of Applied Physics and Materials Engineering, University of Macau, Avenida da Universidade Taipa, Macao 999078, China.
⁸ Research Center for Wide Gap Semiconductor, Peking University, Beijing 100871, China.

PMID: 32786951
DOI: 10.1021/acs.nanolett.0c02462

Abstract

Lead halide perovskites have emerged as excellent optical gain materials for solution-processable and flexible lasers. Recently, continuous-wave (CW) optically driven lasing was established in perovskite crystals; however, the mechanism of low-threshold operation is still disputed. In this study, CW-pumped lasing from one-dimensional CsPbBr₃ nanoribbons (NBs) with a threshold of ∼130 W cm^-2 is demonstrated, which can be ascribed to the large refractive index induced by the exciton-polariton (EP) effect. Increasing the temperature reduces the exciton fraction of EPs, which decreases the group and phase refractive indices and inhibits lasing above 100 K. Thermal management, including reducing the NB height to ∼120 ± 60 nm and adopting a high-thermal-conductivity sink, e.g., sapphire, is critical for CW-driven lasing, even at cryogenic temperatures. These results reveal the nature of ultralow-threshold lasing with CsPbBr₃ and provide insights into the construction of room-temperature CW and electrically driven perovskite macro/microlasers.

Keywords: CsPbBr3; continuous-wave laser; exciton−polariton; low threshold; microlaser; perovskite.