Electric control of spin polarization orientation in a magnetic-electric barrier structure

We investigate spin-dependent transport properties of two-dimensional electron systems modulated by both the stray field from a ferromagnetic metal (FM) stripe and the electrostatic potential (EP) provided by two normal metal Schottky stripes which sandwich the FM stripe. The EP consists of a single barrier and a single well. By switching the gate voltages applied to the Schottky stripes, the barrier and the well exchange their positions. Accordingly, the spatial region, where spin-dependent resonant tunneling happens, is transferred from one side of the FM stripe to the other, resulting in a rotation or a reversal of the spin polarization orientation. (C) 2007 Elsevier B.V. All rights reserved.