Spintronics

Magnetism is dictated by the direction of spin of electrons and increasing research into the use of this property has led to the coining of the term spintronics. The read heads of disk drives already exploit electron spin in an effect called giant magneto Resistance, as does MRAM (see later), which has already seen limited commercial production. An effect called ballistic magneto resistance has recently been demonstrated to have the capability of producing read heads that can deal with storage densities of a terabit per square inch—ten times the density expected in the next generation of hard drives. Commercial application of spintronics in electronics is farther away but the promise is there—a Canadian group recently created a transistor that was switched by the spin of a single electron confined in a quantum dot.