  Centrosymmetric materials with site inversion asymmetries possess hidden spin
polarization, which remains challenging to be converted into spin currents
because the global inversion symmetry is still conserved. This study
demonstrates the spin-polarized DC circular photocurrents (CPC) in
centrosymmetric transition metal dichalcogenides (TMDCs) at normal incidence
without applying electric bias. The global inversion symmetry is broken by
using a spatially-varying circularly polarized light beam, which could generate
spin gradient owing to the hidden spin polarization. The dependences of the CPC
on electrode configuration, illumination position, and beam spot size indicate
an emergence of circulating electric current under spatially inhomogeneous
light, which is associated with the deflection of spin-polarized current
through the inverse spin Hall effect (ISHE). The CPC is subsequently utilized
to probe the spin polarization and ISHE under different excitation wavelengths
and temperatures. The results of this study demonstrate the feasibility of
using centrosymmetric materials with hidden spin polarization and non-vanishing
Berry curvature for spintronic device applications.
