Today, over 125 years since Edwin Hall’s discovery, the Hall effect and its applications remain fertile research areas. Now, two groups have independently measured a new version of the phenomenon based on the internal angular momentum or spin of electrons. Predicted in 1971, the spin Hall effect provides a method of separating electrons with spins pointing in different directions. It is therefore an exciting development for "spintronics" – an emerging area of technology in which both the spin and charge of the electron are manipulated to create new types of microelectronic devices. In particular, the spin Hall effect could allow spintronic devices to be manufactured with the same techniques that are currently used to make semiconductor devices.
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