Spin-to-Charge Conversion in Bi Films and Bi/Ag Bilayers

Thermally injected pure spin current phenomena have been investigated in Bi/Y_{3}Fe_{5}O_{12} and Bi/Ag/Y_{3}Fe_{5}O_{12} structures at room temperature. We show that although pure spin current has been injected into the Bi layer and the Bi/Ag bilayer, there is little detectable signal of spin-to-charge conversion, except the distinctive Nernst signal from the Bi layer, in sharp contrast to the inverse Rashba-Edelstein effect claimed in these systems.