  We investigate the intrinsic orbital Hall conductivity (OHC) and spin Hall
conductivity (SHC) in a bismuth semimetal, by employing an sp-orbital
tight-binding model. We report a notable difference between the anisotropy of
OHC and SHC whose orbital and spin polarizations lie within the basal plane. We
do not observe a substantial correlation between the orbital and spin Berry
curvatures with spin-orbit coupling (SOC) at the Fermi energy, disproving the
correlation between OHC and SHC in a strong SOC regime. We argue the huge SHC
in a Bi semimetal is attributed to its gigantic SOC which strongly affects the
hybridization of the p orbitals, despite its relatively small magnitude of OHC.
We hope the distinct anisotropy of OHC and SHC provides a feasible means to
differentiate between the two effects in experiments.
