@article{7bd8efe522fa4ddfa5c3ce6358c26984,
title = "Carrier–Phonon Interaction Induced Large Negative Thermal-Optic Coefficient at Near Band Edge of Quasi-2D (PEA)2PbBr4 Perovskite",
abstract = "The soft and polar nature of quasi-2D (PEA)2PbBr4 perovskite, and robust photo-generated excitons lead exciton-polaritons and exciton-polarons as the important phenomena near the band edge for application in the lighting aspect. In this work, a convenient methodology is proposed based on the polariton resonant modes in temperature-dependent (77 K to RT) spectroscopy, and investigate the effect of these quasi-particles on refractive index dispersion. The large binding energy (≈335 meV) of quasi-2D excitons is obtained by the reflectance measurements at 77 K. Stable exciton-polaritons and exciton-polarons are confirmed by energy dispersions and the observation of self-trapped exciton-polaron state, respectively. Furthermore, the large negative thermal-optic coefficient due to damping effect of exciton-phonon scattering is observed. The phenomenon is opposite to those observed in conventional semiconductors (e.g., Si, Ge, GaN, AlN, GaAs, AlAs, and ZnO etc.). The observed stable negative thermal-optic coefficients from 160 K to RT indicate that the quasi-2D perovskite can be used as a phase compensator for conventional semiconductor materials.",
author = "Wu, {Sheng Chan} and Wu, {Chun Sheng} and Chien, {Ching Hang} and Zhang, {Yu Wei} and Yang, {Chung Xian} and Cheng Liu and Li, {Ming Hsien} and Lin, {Chen Fu} and Wu, {Yu Hao} and Lin, {Bi Hsuan} and Chou, {Yu Hsun} and Chang, {Yia Chung} and Peter Chen and Hsu, {Hsu Cheng}",
note = "Funding Information: The authors thank the financial support from Hierarchical Green‐Energy Materials (Hi‐GEM) Research Center, from The Featured Areas Research Center Program within the framework of the Higher Education Sprout Project by the Ministry of Education (MOE) and the Ministry of Science and Technology (MOST 111‐2112‐M‐006‐023‐MY3, MOST 111‐2112‐M‐001‐069, MOST 111‐2221‐E‐006‐061‐MY2, MOST 111‐2113‐M‐006‐009, MOST 110‐2634‐F‐006 ‐017, MOST 109‐2124‐M‐006‐001, MOST 111‐2112‐M‐213‐020, MOST 109‐2222‐E‐260‐001‐MY3, Young Scholar Fellowship Program MOST 111‐2636‐M‐006 ‐025) in Taiwan. This research was also supported in part by Higher Education Sprout Project, Ministry of Education to the Headquarters of University Advancement at National Cheng Kung University. The authors also gratefully acknowledge the use of code XRD005101 of the machine equipment belonging to the Core Facility Center of National Cheng Kung University. Publisher Copyright: {\textcopyright} 2023 Wiley-VCH GmbH.",
year = "2023",
month = jun,
day = "19",
doi = "10.1002/adfm.202213427",
language = "English",
volume = "33",
journal = "Advanced Functional Materials",
issn = "1616-301X",
publisher = "Wiley-VCH Verlag",
number = "25",
}