Halide pervoskites are an important class of semiconducting materials which hold great promise for optoelectronic applications. In this work we investigate the relationship between vibrational anharmonicity and dynamic disorder in this class of solids. Via a multi-scale model parameterized from first-principles calculations, we demonstrate that the non-Gaussian lattice motion in halide perovskites is microscopically connected to the dynamic disorder of overlap fluctuations among electronic states. This connection allows us to rationalize the emergent differences in temperature-dependent mobilities of prototypical MAPbI3 and MAPbBr3 compounds across structural phase-transitions, in agreement with experimental findings. Our analysis suggests that the details of vibrational anharmonicity and dynamic disorder can complement known predictors of electronic conductivity and can provide structure-property guidelines for the tuning of carrier transport characteristics in anharmonic semiconductors.
@article{arxiv.2305.13682,
title = {Correlated Anharmonicity and Dynamic Disorder Control Carrier Transport in Halide Perovskites},
author = {Maximilian J. Schilcher and David J. Abramovitch and Matthew Z. Mayers and Liang Z. Tan and David R. Reichman and David A. Egger},
journal= {arXiv preprint arXiv:2305.13682},
year = {2023}
}