The anomalous Hall conductivity in magnetic Weyl semimetals scales linearly with the momentum separation between Weyl nodes, establishing a geometric paradigm for three-dimensional Hall responses. Here, we discover an analogous phenomenon in the spin Hall effect: a quantized spin Hall conductivity (SHC) in nodal-ring semimetals that scales linearly with the nodal-ring radius $R$. From an ideal model with a single nodal ring, we derive analytically that the SHC inside the spin-orbit-coupled gap obeys ${\sigma }_{\alpha \beta }^{S,3\mathrm{D}}={\sigma }_0^{S,2\mathrm{D}}(\pi R/2\pi )$, where ${\sigma }_0^{S,2\mathrm{D}}=(e^2/h)(\hslash /2e)$ is the two-dimensional quantum spin Hall conductance. Crucially, the symmetry of the spin-orbit coupling acts as an independent switch: Rashba coupling generates purely conventional SHC components, while Weyl coupling additionally activates unconventional ones, providing separate control over response magnitude and tensor symmetry. We validate this principle in yttrium nitride, where strain tunes $R$ and symmetry breaking toggles between response types. Our Letter establishes a new paradigm for engineering quantized geometric responses in three dimensions, opening pathways to tailored spin-orbit functionalities.

Close

PrevNext

View figure in article

• Spin Hall effect
• Spintronics
• Transport phenomena
• 3-dimensional systems
• Topological materials
• First-principles calculations
• Tight-binding model
• k dot p method