Infrared and terahertz studies of phase transitions in the CH.sub.3./sub.NH.sub.3./sub.PbBr.sub.3./sub. perovskite

0573779 - FZÚ 2024 RIV US eng J - Journal Article
Železný, Jakub - Kadlec, Christelle - Kamba, Stanislav - Repček, Dalibor - Kundu, S. - Saidaminov, M.I.
Infrared and terahertz studies of phase transitions in the CH₃NH₃PbBr₃ perovskite.
Physical Review B. Roč. 107, č. 17 (2023), č. článku 174113. ISSN 2469-9950. E-ISSN 2469-9969
R&D Projects: GA MŠMT(CZ) EF16_019/0000760; GA ČR(CZ) GA21-06802S
Grant - others:OP VVV - SOLID21(XE) CZ.02.1.01/0.0/0.0/16_019/0000760
Institutional support: RVO:68378271
Keywords : infrared spectroscopy * photovoltaic materials * phase transitions
OECD category: Condensed matter physics (including formerly solid state physics, supercond.)
Impact factor: 3.7, year: 2022
Method of publishing: Limited access
https://doi.org/10.1103/PhysRevB.107.174113

We investigated the influence of two structural phase transitions in methylammonium lead tri-bromide CH3NH3PbBr3 (MAPbBr3) single crystals on the activity of polar phonons using time-domain THz transmission and far infrared (IR) reflectance spectra. The fitting using the Lorentz model of damped harmonic oscillators also enables us to determine all the polar phonon parameters, IR response functions, and their temperature dependence. The fit of the far IR spectra provides a nearly perfect quantitative description of the measured reflectance at room temperature using three phonons. On cooling, three IR active phonons of the cubic and tetragonal structures split into 15 separate bands, signaling the transformation to the orthorhombic phase below 150 K. This result is compared with the factor group analysis of the polar phonons in all three crystallographic phases.
Permanent Link: https://hdl.handle.net/11104/0344140