30-07-2009, 04:07 PM
In a world of ubiquitous presence of electrons can you imagine any other field displacing it? It may seem peculiar, even absurd, but with the advent of spintronics it is turning into reality.
In our conventional electronic devices we use semi conducting materials for logical operation and magnetic materials for storage, but spintronics uses magnetic materials for both purposes. These spintronic devices are more versatile and faster than the present one. One such device is spin valve transistor.
Spin valve transistor is different from conventional transistor. In this for conduction we use spin polarization of electrons. Only electrons with correct spin polarization can travel successfully through the device. These transistors are used in data storage, signal processing, automation and robotics with less power consumption and results in less heat. This also finds its application in Quantum computing, in which we use Qubits instead of bits.
Spintronics came into light by the advent of Giant Magneto Resistance (GMR) in 1988. GMR is 200 times stronger than ordinary Magneto Resistance. It results from subtle electron - spin effects in ultra multilayers of magnetic materials that cause a huge change in electrical resistance.