Physicists Observe Elusive Electron Hall Effect
The spin Hall Effect, named after American physicist Edwin Hall, was discovered in 1879. Today, with the coming of semi-conductors, the Hall effect is used in a variety of devices. This Hall effect is produced by the charge of an electron. There is another way to produce the effect and that is through the spin of an electron.
The Hall effect comes in two varieties itself: spin and charge.
In 1879, when Edwin Hall was monitoring an electric current — that is, a moving charge — in a magnetic field, he observed a measurable voltage.
He attributed the effect to the force a magnetic field exerts on moving charge carriers, pushing them to one side of the conductor and building up charge on that side.
The charge buildup ultimately balances the magnetic force, producing a measurable voltage between opposite sides of the conductor.
Today’s sensors and electronics make liberal use of this plain-vanilla “Hall effect.”
The spin Hall Effect was first predicted in 1971 by Russian physicists M.I. D’yakonov and V. I. Perel; they predicted that current-carrying electrons with opposite spins would move toward opposite sides of a semiconductor wire. The prediction hasn’t been proved/observed until now (2004).
Potential applications of the spin Hall effect may include “sensing technologies, potential pathways towards shuttling spin information in semiconductors, as well as quantum computing and quantum communication,” said Awschalom, who directs the UCSB Center for Spintronics and Quantum Computation.
But he added, “The most exciting aspect of this finding is that you don’t know exactly where it’s going to lead.”