nl0c02462_si_001.pdf (2.31 MB)
Role of the Exciton–Polariton in a Continuous-Wave Optically Pumped CsPbBr3 Perovskite Laser
journal contribution
posted on 2020-08-19, 23:03 authored by 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 ZhangLead
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.