University ‘Spin-Doctors’ measure and control electrons

  • Dover (DE) - Researchers from the University of Delaware and Cambridge NanoTech claim they can measure and transport the spin of electrons in silicon.  Using a small silicon chip, the scientists are able to send electrons down a small wire and then measure and change the direction of spin.  The discovery could be a boon to the nascent quantum computer industry because silicon is the most popular element used in computers.


    Ian Appelbaum, assistant professor of electrical and computer engineering, is the lead author of a report recently published in the scientific journal Nature.  His discovery is in the little-known field of ‘spintronics’ which uses electron spin to make potentially much faster quantum computers.  Traditionally it’s fairly easy to transport electrons and charges through a computer chip, but scientists have had difficulty in doing it in room-temperature everyday silicon.

    Electron spin, n scientific terms electron angular momentum, is typically defined as “spin up” or “spin down”.  By harnessing the extra information of spin, future electronics could store and process data with the same set of electrons.  Currently your average computer merely tracks electrical charges as being “on” or “off”.

    But computer makers will have to clear another hurdle before Appelbaum’s invention becomes reality.  Electron spin is typically slowed or stopped as it bumps into other electrons.  This so-called “spin Coulomb drag” in effect diffuses the spin through a group of electrons.