Published on Jun 05, 2023
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.Two experiments in 1920's suggested spin as an additional property of the electron. One was the closely spaced splitting of Hydrogen spectralines, called fine structure. The other was Stern -Gerlach experiment, which in 1922 that a beam of silver atoms directed through an inhomogeneous magnetic field would be forced in to two beams.
These pointed towards magnetism associated with the electrons. Spin is the root cause of magnetism that makes an electron tiny magnet. Magnetism is already been exploited in recording devices. Where data is recorded and stored as tiny areas of magnetized iron or chromium oxide. To access that information the head detects the minute changes in magnetic field. This induces corresponding changes in the head's electrical resistance - a phenomenon called Magneto Resistance.
