Patent ID: 6456523
Filing Date: 2002-09-24
Classification: B82Y,G01R,G11B,G11C,H01F,H01L

Abstract:
A ferromagnetic double quantum well tunneling magnetoresistance device including a sandwich structure comprising, in order:a first electrode; a first tunneling barrier layer; a first two-dimensional quantum well layer of ferromagnetic material; a second tunneling barrier layer; a second two-dimensional quantum well layer of ferromagnetic material; a third tunneling barrier layer; and a second electrode; wherein each of the first two-dimensional quantum well layer and the second two-dimensional quantum well layer is comparable to or thinner than a de Broglie wavelength of carriers in a three-dimensional electron system of the ferromagnetic material, whereby the carriers are quantum-confined; wherein a first interface between the first two-dimensional layer of ferromagnetic material and the second tunneling barrier layer is substantially atomically flat and abrupt; wherein a second interface between the second two-dimensional layer of ferromagnetic material and the second tunneling barrier layer is substantially atomically flat and abrupt; and wherein each of the first tunneling barrier layer, the second tunneling barrier layer, and the third tunneling barrier layer includes a respective barrier thickness that enables the carriers to tunnel therethrough; whereby a change in direction of magnetizations in the first two-dimensional quantum well layer and the second two-dimensional quantum well layer causes carriers to tunnel between them, thereby producing a change in magnetoresistance across them.