Spin textures in curved paths on a curved surface

Abstract: This study investigates the quantum dynamics of a spin-1/2 particle confined to a curved path from the dynamics of a two-dimensional curved thin-layer system incorporating spin connection contributions. We demonstrate that the geodesic curvature, normal curvature, and geodesic torsion of the curve govern the emergent non-Abelian gauge potential and effective scalar potential in the system's Hamiltonian. The resulting spin precession dynamics induced by the gauge potential are analyzed, revealing that the rotation angle of spin orientation along a surface boundary and the pseudo-magnetic flux are topologically governed by the surface geometry. Spin texture evolution along helices illustrates distinct behaviors under geodesic versus non-geodesic propagation. Further, spin evolution in a closed trajectory-Viviani's curve, exemplifies the surface-dependent spin orientation and path-ordering sensitivity of the non-Abelian gauge potential. Our theory establishes a framework for spin-state manipulation via engineered nanostructured channels, enabling novel topological quantum control strategies.