Anticipation of Large Intrinsic Spin Hall Conductivity in Mercury Chalcogenides: A First-Principles Study

The report carried out detailed first-principle calculations of Mercury chalcogenides (HgX; X = Te, Se and S) using density functional theory, verifying the bulk band inversion property with different exchange-correlation functionals. The Wannier function method is used to study the non-trivial topology of HgX systems, spin Berry curvature, and intrinsic spin Hall conductivity. Quantized intrinsic spin Hall conductivity is observed in the HgX systems. Large intrinsic spin Hall conductivity is found in the systems due to a strong spin Berry curvature accumulation near the triply degenerate points in the Brillouin zone. Calculation shows that the intrinsic spin Hall conductivity for all three HgX systems has stable plateaus, with Mercury Telluride having a maximum width of up to 1.05 eV. The maximum intrinsic spin Hall conductivity of –931$\hslash$/e (${\mathrm{Scm}}^{-1}$) is obtained in mercury sulfide, higher than the reported values for spin Hall conductivity and the plateau width in typical topological insulators such as ${\text{Bi}}_2{\text{Se}}_3$, ${\text{Bi}}_2{\text{Te}}_3$, and ${\text{Sb}}_2{\text{Se}}_3$ as well as in transition metal pnictides (TaX, X = As, P and N) and transition metal iridates.