title: 2D Behaviors of Excitons in Cesium Lead Halide Perovskite Nanoplatelets.
abstract: Fundamental to understanding and predicting the optoelectronic properties of semiconductors is the basic parameters of excitons such as oscillator strength and exciton binding energy. However, such knowledge of CsPbBr3perovskite, a promising optoelectronic material, is still unexplored. Here we demonstrate that quasi-two-dimensional (quasi-2D) CsPbBr3nanoplatelets (NPLs) with 2D exciton behaviors serve as an ideal system for the determination of these parameters. It is found that the oscillator strength of CsPbBr3NPLs is up to 1.18 × 104, higher than that of colloidal II-VI NPLs and epitaxial quantum wells. Furthermore, the exciton binding energy is determined to be of ∼120 meV from either the optical absorption or the photoluminescence analysis, comparable to that reported in colloidal II-VI quantum wells. Our work provides physical understanding of the observed excellent optical properties of CsPbBr3nanocrystals and would benefit the prediction of high-performance excitonic devices based on such materials.
authors.affiliation: State Key Laboratory of Silicon Materials, School of Materials Science and Engineering, Zhejiang University , Hangzhou, Zhejiang 310027, P. R. China.
authors.forename: Jing
authors.initials: J
authors.lastname: Li
authors.affiliation: Hefei National Laboratory for Physical Sciences at the Microscale, Key Laboratory of Strongly-Coupled Quantum Matter Physics of Chinese Academy of Sciences, Department of Chemical Physics, University of Science and Technology of China , Hefei, Anhui 230026, P. R. China.
authors.forename: Laihao
authors.initials: L
authors.lastname: Luo
authors.affiliation: Hefei National Laboratory for Physical Sciences at the Microscale, Key Laboratory of Strongly-Coupled Quantum Matter Physics of Chinese Academy of Sciences, Department of Chemical Physics, University of Science and Technology of China , Hefei, Anhui 230026, P. R. China.
authors.forename: Hongwen
authors.initials: H
authors.lastname: Huang
authors.affiliation: Hefei National Laboratory for Physical Sciences at the Microscale, Key Laboratory of Strongly-Coupled Quantum Matter Physics of Chinese Academy of Sciences, Department of Chemical Physics, University of Science and Technology of China , Hefei, Anhui 230026, P. R. China.
authors.forename: Chao
authors.initials: C
authors.lastname: Ma
authors.affiliation: State Key Laboratory of Silicon Materials, School of Materials Science and Engineering, Zhejiang University , Hangzhou, Zhejiang 310027, P. R. China.
authors.forename: Zhizhen
authors.initials: Z
authors.lastname: Ye
authors.affiliation: Hefei National Laboratory for Physical Sciences at the Microscale, Key Laboratory of Strongly-Coupled Quantum Matter Physics of Chinese Academy of Sciences, Department of Chemical Physics, University of Science and Technology of China , Hefei, Anhui 230026, P. R. China.
authors.forename: Jie
authors.identifier: http://orcid.org/0000-0002-8812-0298
authors.initials: J
authors.lastname: Zeng
authors.affiliation: State Key Laboratory of Silicon Materials, School of Materials Science and Engineering, Zhejiang University , Hangzhou, Zhejiang 310027, P. R. China.
authors.forename: Haiping
authors.identifier: http://orcid.org/0000-0001-8246-0286
authors.initials: H
authors.lastname: He