Impact of anharmonicity on the carrier mobility of the Pb-free CsSnBr 3 perovskite

This study computes charge carrier mobilities in the lead-free perovskite CsSnBr${}_{3}$ using temperature-dependent effective potentials and $a\phantom{\rule{0}{0ex}}b$ $i\phantom{\rule{0}{0ex}}n\phantom{\rule{0}{0ex}}i\phantom{\rule{0}{0ex}}t\phantom{\rule{0}{0ex}}i\phantom{\rule{0}{0ex}}o$ Boltzmann transport equations. It shows that the harmonic approximation overestimates mobilities [106/256 cm${}^{2}$/(Vs)] compared to anharmonic results [59/145 cm${}^{2}$/(Vs)], due to neglected scattering from soft modes. This work establishes a first-principles workflow for modeling carrier transport in anharmonic perovskites, improving predictive design of efficient halide perovskite solar cells.