Spin Hall effect and Nernst effect in FePt/Au multi-terminal devices with different Au thicknesses

The spin-Hall effect and the Nernst effect were investigated in multi-terminal devices consisting of an FePt perpendicular spin polarizer and a Au Hall cross with different Au thicknesses. As the thickness of the Au Hall cross increased from 10 nm to 20 nm, the spin-Hall angle (αHαH) was significantly reduced. The significant reduction of the spin-Hall angle indicates that the interface and/or surface scattering of the electron spins play a crucial role for the large αHαH. The voltage change due to the Nernst effect also decreased with increasing the thickness of the Au Hall cross.