Spin Hall conductivity in Pt films under tetragonal and orthorhombic distortions

Highlights: • The spin-to-charge conversion efficiency in Pt thin films can be enhanced by deformations. • The sensitivity of the spin Hall conductivity can be as large as 8.6% for every 1% of strains. • The underlying mechanism is the electronic band deformations. Noble metal Pt with the face-centered-cubic structure is distorted to tetragonal and orthorhombic structures in order to mimic thin films grown on flexible substrates and bending. The electronic structures from the fully relativistic treatment of the kinetic terms were obtained and followed by projecting the extensive states into the localized Wannier orbitals with a minimum basis. The spin Hall conductivity (SHC) was then obtained with the help of the concept of the Berry curvature. We find that tensile strains in-plane can enhance the SHC while the compressive ones reduce the ${\sigma }_{xy}^z$ component of the SHC. The variation of SHC can be as large as 8.6% for every 1% of the strains. Our work shows the possibility of tuning the SHC in metals, which can be utilized in spintronic devices.