Spin-valve effects in a semiconductor field-effect transistor: A spintronic device

We present a spintronic semiconductor field-effect transistor. The injector and collector contacts of this device were made from magnetic permalloy th in films with different coercive fields so that they could be magnetized ei ther parallel or antiparallel to each other in different applied magnetic f ields. The conducting medium was a two-dimensional electron gas (2DEG) form ed in an AlSb/InAs quantum well. Data from this device suggest that its res istance is controlled by two different types of spin-valve effect: the firs t occurring at the ferromagnet-2DEG interfaces; and the second occurring in direct propagation between contacts. [S0163-1829(99)04335-0].