Professor John Gregg

Abstract:

A burgeoning trend in spin electronics is the development of spin-sensitive semiconductor devices. Implementing spin-polarized carriers in semiconductors expands potential device functionality by differentiating between up and down spin carriers in both the conduction and valence bands. This spin selectivity may be realized by using magnetic semiconductors or by employing external spin-selective ferromagnets to inject spin-polarized current into nonmagnetic semiconductors. As the length scales are reduced, ferromagnetic single electron devices become feasible.

Abstract:

A susceptibility sensor for detecting relative movement between an inhomogeneously-shaped object (80) to be sensed, and the sensor, comprising: a Robinson marginal oscillator (20) having a plurality of electrical properties; a tank circuit (30) connected to the Robinson marginal oscillator and …

Abstract:

The realization of many future spintronic devices requires efficient spin injection into semiconductor structures. A Critical considerations include interfacial intermixing of the metallic components and oxygen with Si, and the conditions for Schottky barrier formation. Both impact the design of a silicon-based spin transistor, which tunnel injects carriers from a ferromagnetic emitter into the Si base and then tunnel-collects them via a ferromagnetic collector. A discussion of the characteristics of this spin tunnel transistor will be presented, including its behavior and magnetic sensitivity. © 2004 Elsevier B.V. All rights reserved.