The Landé factors of electrons and holes in lead halide perovskites: universal dependence on the band gap.

Kirstein, E; Yakovlev, D R; Glazov, M M; Zhukov, E A; Kudlacik, D; Kalitukha, I V; Sapega, V F; Dimitriev, G S et al. · Nat Commun · 2022

basic_science · Level V

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Abstract

The Landé or g-factors of charge carriers are decisive for the spin-dependent phenomena in solids and provide also information about the underlying electronic band structure. We present a comprehensive set of experimental data for values and anisotropies of the electron and hole Landé factors in hybrid organic-inorganic (MAPbI<sub>3</sub>, MAPb(Br<sub>0.5</sub>Cl<sub>0.5</sub>)<sub>3</sub>, MAPb(Br<sub>0.05</sub>Cl<sub>0.95</sub>)<sub>3</sub>, FAPbBr<sub>3</sub>, FA<sub>0.9</sub>Cs<sub>0.1</sub>PbI<sub>2.8</sub>Br<sub>0.2</sub>, MA=methylammonium and FA=formamidinium) and all-inorganic (CsPbBr<sub>3</sub>) lead halide perovskites, determined by pump-probe Kerr rotation and spin-flip Raman scattering in magnetic fields up to 10 T at cryogenic temperatures. Further, we use first-principles density functional theory (DFT) calculations in combination with tight-binding and k ⋅ p approaches to calculate microscopically the Landé factors. The results demonstrate their universal dependence on the band gap energy across the different perovskite material classes, which can be summarized in a universal semi-phenomenological expression, in good agreement with experiment.