The spin Hall conductivity in the hole-doped bilayer Haldane-Hubbard model with odd-parity ALM

Abstract

Spin current generated electrically is among the core phenomena of spintronics for driving high-performance spin device applications. Here, on the basis of systematic investigations for the hole doped single-layer Haldane-Hubbard(HH) model, we propose a new bilayer HH model to realize the compensated odd-parity spin splitting and the $T$-even spin Hall conductivity where the two layers are connected by the time reversal transformation. Our results show that the vanishing layer-dependent electric potential $V_{L}$ gives rise to odd-parity ALM protected by the combined symmetry $TM_{xy}$ with $T$ and $M_{xy}$ being the time reversal and mirror reflection perpendicular to $z$ axis, and the $T$-even spin Hall conductivity simultaneously. In addition, though the staggered magnetization within each layer is substantially impacted by the layer-dependent electric potential, small $V_{L}$'s only bring negligible changes to the net magnetization and the spin Hall conductivity, indicating that the alternating spin splitting in momentum space and the spin Hall conductivity are insusceptible to external elements. Most importantly, our work provides a general framework for the simultaneous realization of the compensated odd-parity spin splitting in momentum space and the spin Hall conductivity in collinear magnets, in terms of stacked multi-layer systems.