Spin Injection Into Ferromagnetic Metal From Heavy Metal Owing to Spin Hall Effect

When a current flows through a heavy metal (HM), the spin of the current carriers is polarized by the spin Hall effect (SHE). In a junction of a HM and a ferromagnetic metal (FM), the spin current flows into the FM from the HM and gives spin-transfer torque to the magnetic moments of the FM. We calculate the spin current in a layer of HM/FM with the SHE. We use a spin-resolved electrochemical potential including the SHE in the calculation of the spin current. The spin current flowing into the FM depends strongly on the thickness of the HM.