Low-field magnetocurrent above 200% in a spin-valve transistor at room temperature

A spin-valve transistor (SVT) that employs hot electrons is shown to exhibi t a huge magnetotransport effect at room temperature in small magnetic fiel ds. The SVT is a ferromagnet-semiconductor hybrid structure in which hot el ectrons are injected into a NiFe/Au/Co spin valve, and collected on the oth er side with energy and momentum selection. This makes the collector curren t extremely sensitive to spin-dependent scattering. The hot-electron curren t output of the device changes by more than a factor of three in magnetic f ields of only a few Oe, corresponding to a magnetocurrent above 200% at roo m temperature. (C) 2000 Elsevier Science B.V. All rights reserved.