Rashba spin-splitting driven inverse spin Hall effect in MnBi2Te4.

The inverse spin Hall effect is a critical method for detecting spin Hall conductivity. Unearthing the physical relationship between electronic structure and spin Hall conductivity is conducive to establishing an intrinsic link between microstructure and macroscopic phenomena. Here, we report MnBi₂Te₄ as an ideal candidate: a stable, inversion symmetry-broken magnetic topological insulator for investigating the intrinsic correlation between spin Hall conductivity signal reversal and electronic structure. The valence band exhibits a significant Rashba spin splitting, with a magnitude reaching up to 4.61 eV/Å. We identify robust topological properties independent of Rashba and Lifshitz spin-splitting types. Moreover, transitioning the spin-splitting type not only widens the bulk band gap, enhancing the spin Hall conductivity plateau, but also triples the intrinsic spin Hall conductivity value. We propose the inverse spin Hall effect that is tunable by spin-splitting types, thereby advancing the research on the microscopic electronic mechanisms of spin current detection. The spin Hall effect facilitates the generation and detection of spin currents and is expected to play an important role in future spintronic devices. Here, the authors theoretically investigate the presence of Rashba spin splitting for MnBi2Te4 and the relationship with an inverse spin Hall effect also present in the system. [ABSTRACT FROM AUTHOR]