Unexpectedly Strong Auger Recombination in Halide Perovskites

The emergence of halide perovskites for photovoltaic applications has triggered great interest in these materials for solid-state light emission. Higher order electron-hole recombination processes can critically affect the efficiency of such devices. In the present work, the Auger recombination coefficients are computed in the prototypical halide perovskite, CH3NH3PbI3 (MAPbI(3)), using first-principles calculations. It is demonstrated that Auger recombination is responsible for the exceptionally high third-order recombination coefficient observed in experiment. The large Auger coefficient is attributed to a coincidental resonance between the bandgap and interband transitions to a complex of higher-lying conduction bands. Additionally, it is found that the distortions of PbI6 octahedra contribute significantly to the high Auger coefficient, offering potential avenues for materials design.