**Unveiling carrier recombination mechanisms in halide perovskites from first-principles calculations**

Host: Cyrus Dreyer

Halide perovskites are highly efficient optoelectronic materials; the power conversion efficiency of perovskite solar cells has reached 25.2%, being already comparable with that of single-crystalline silicon cells (26.1%). To understand the fundamental physics behind the superior performance, carrier recombination mechanisms are crucial. In recent years, we have developed a full set of first-principles approaches that allow to quantitatively compute the carrier recombination rates based on density functional theory and to understand the underlying recombination mechanisms. I will present a number of critical insights into the radiative [1-2] and nonradiative [3-7] recombination mechanisms in halide perovskites obtained by applying our methodology to this technologically important system.

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