8 Spintronics — Spin - Based Electronics

Spintronics is an acronym for a spin transport electronics and was originally used as a name for the Defense Advanced Research Projects Agency (DARPA) program. In 1994, DARPA started to develop magnetic field sensors and memory based on the giant magnetoresistance (GMR) effect and spindependent tunneling. The overall goal for the Spintronics program was to create a new generation of electronic devices where the spin of the carriers would play a crucial role in addition to or in place of the charge. Spintronic devices can be used as magnetic memories, magnetic field sensors, spin-based switches, modulators, isolators, transistors, diodes, and perhaps some novel devices without conventional analogues that can perform logic functions in new ways. Spintronics brings together specialists in semiconductors, magnetism, and optical electronics studying spin dynamics and transport in semiconductors, metals, superconductors, and heterostructures. As always, the key question is whether any potential benefit of such technology will be worth the production costs. S.A. Wolf Defense Advanced Research Projects Agency and Naval Research Laboratory