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IBM Tech Detects & Changes Spin of Single Electron

Posted by CmdrTaco on from the i-got-hundreds-of-those-things dept.

An anonymous reader writes "Looks like we have another step forward in Quantum Computing - IBM has discovered how to detect and change the spin of a single electron. Won't be long before we're all solving impossible encryption problems. "

5 of 334 comments (clear)

  1. Not Electrons by Da+Twink+Daddy · · Score: 5, Informative

    Whew, okay. After I RTFA I realized they hadn't done the impossible, just the really hard. IBM can measured the energy required to change the spin of a single atom not a single electron. (A prerequisite of this, of course, is detecting the spin of a single atom; but that's not that difficult with electron microscopes.)

  2. Stern-Gerlach experiment by Aardpig · · Score: 5, Informative

    IBM has discovered how to detect and change the spin of a single electron.

    Measuring the spin of electrons bound to atoms was first achieved in the famous 1922 Stern-Gerlach experiment, a key stage in the discovery and understanding of quantum spin.

    However, to quote from this discussion of the experiment, the Stern-Gerlach technique cannot be used to measure free electron spin because 'The spreading of the electron wave packet washes out the separation effect due to the electron spin'. Therefore, it appears that IBM's discovery is significant.

    --
    Tubal-Cain smokes the white owl.
  3. Re:Innovation by EyeSavant · · Score: 5, Informative

    Yeah IBM do some really good stuff. The IBM research has taken over from bell labs as being one of the best research labs around. It is such a shame bell labs went from being amazing to depressing but that is a different story. At IBM they have invented copper interconnects (seen in a lot of CPUs these days). They invented Silicon on Insulator transistors (seen in a lot of modern CPUs as well). They have done some nice work on carbon nanotubes (those have a long way to go though), and now spintronics (this has a really long way to go as well). They do a lot of really good stuff at IBM.

  4. CmdrTaco mistake. by Futurepower(R) · · Score: 5, Informative


    Okay, one answer is that CmdrTaco got it wrong. He said, "IBM Tech Detects & Changes Spin of Single Electron". He should have said, "IBM Tech Detects & Changes Spin of Single Atom". Huge difference.

    --
    Bush's education improvements were partly fraud

  5. Re:Hmmmm. by BabyDave · · Score: 5, Informative

    As I recall, Heisenberg states the impossibility of measuring both the position and momentum of a particle at the same time.

    Yes, but it's more general.

    In QM, you measure a property of an object by applying an "operator" (you put in a function, and it spits out another function) to its wavefunction. Heisenberg said[*] that certain pairs of operators don't commute (meaning order is important - AB != BA), and so some pairs of properties can't be measured together.

    "Position and momentum" is a particular example of a pair, as is "different components of angular momentum" (L_x and L_z, say). I can't remember how 'spin' fits into things, though ...

    [*]Pedantry: Yes, I know Heisenberg talked about matrices, Schrodinger about operators.