Intrinsic Exciton Transport and Recombination in Single-Crystal Lead Bromide Perovskite
Photogenerated carrier transport and recombination in metal halide perovskites are critical to device performance. Despite considerable efforts, sample quality issues and measurement techniques have limited the access to their intrinsic physics. Here, by utilizing high-purity CsPbBr<sub>3</sub> single crystals and contact-free transient grating spectroscopy, we directly monitor exciton diffusive transport from 26 to 300 K. As the temperature (<i>T</i>) increases, the carrier mobility (μ) decreases rapidly below 100 K wtih a μ ∼ <i>T</i><sup>-3.0</sup> scaling, and then follows a more gradual μ ∼ <i>T</i><sup>-1.7</sup> trend at higher temperatures. First-principles calculations perfectly reproduce this experimental trend and reveal that optical phonon scattering governs carrier mobility shifts over the entire temperature range, with a single longitudinal optical mode dominating room-temperature transport. Time-resolved photoluminescence further identifies a substantial increase in exciton radiative lifetime with temperature, attributed to increased exciton population in momentum-dark states caused by phonon scattering. Our findings unambiguously resolve previous theory-experiment discrepancies, providing benchmarks for future optoelectronic design.
Authors
- Dongxin Ma (ORCID: https://orcid.org/0000-0002-9790-5951)
- Qihua Xiong (ORCID: https://orcid.org/0000-0002-2555-4363)
- Ping‐Heng Tan (ORCID: https://orcid.org/0000-0001-6575-1516)
- Miao‐Ling Lin (ORCID: https://orcid.org/0000-0001-5838-8237)
- Yunfei Bai (ORCID: https://orcid.org/0000-0002-4088-4117)
- Heng Wu (ORCID: https://orcid.org/0000-0002-2582-6322)
- Tao Sun (ORCID: https://orcid.org/0000-0003-0671-2570)
- Luyi Yang (ORCID: https://orcid.org/0000-0001-6260-1395)
- Danlei Zhu (ORCID: https://orcid.org/0009-0004-0614-7983)
- Sheng Meng (ORCID: https://orcid.org/0000-0002-1553-1432)
- Haochen Zhang (ORCID: https://orcid.org/0000-0002-2774-5868)
- Yubin Wang (ORCID: https://orcid.org/0000-0003-4454-7190)
- Yaxian Wang (ORCID: https://orcid.org/0000-0003-4790-2880)
- Yang Cui (ORCID: https://orcid.org/0000-0002-0768-4973)
- Y. G. Shi
- Zhixuan Bi
Institutions
- Chinese Academy of Sciences (CN)
- FZU ‒ Institute of Physics of the Academy of Sciences of the Czech Republic (CZ)
- Institute of Semiconductors (CN)
- Beijing Academy of Quantum Information Sciences (CN)
- National Laboratory for Superconductivity (CN)
- State Key Laboratory of Low-Dimensional Quantum Physics
- Ministry of Industry and Information Technology (CN)
- Tsinghua University (CN)
Publication Details
- Journal
- ACS Nano
- Published
- 2025-05-19
- DOI
- https://doi.org/10.1021/acsnano.5c03274
- Citations
- 4
- Primary Topic
- Perovskite Materials and Applications
- Type
- article
- Field-Weighted Citation Impact
- 2.92
Funders
- National Natural Science Foundation of China
- Beijing Municipal Natural Science Foundation
- National Key Research and Development Program of China