Effect of nonmagnetic spacer on hot-electron transport in the spin-valve transistor

The effect of the nonmagnetic (NM) spacer on hot-electron transport in the spin-valve transistor (SVT) is reported. Au, Cu and Ta have been used in the nonmagnetic spacer of the Ni80Fe20/NM/Co spin-valve base. Devices with Cu show 1.5 times higher output current than those with Au at comparable magnetic sensitivity. Structures with Ta spacer show a reduction in the magnetocurrent (MC) from 300% to 9% while the transfer ratio is reduced by three orders of magnitude compared to devices with Au and Cu. The collector current of the spin-valve transistor with Cu spacer increases linearly with emitter current, and a collector current of 64 (mu)A is achieved.