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Using Superconductors as Insulators

Posted by ryuzaki0 on from the skimpy-but-good dept.

slambo writes "Nando Times is reporting today that Swiss scientists have discovered a way to turn a superconductor into an insulator by applying an electric current to it. " Almost zero details in the story itself, but the whole idea really appeals to me. Anyone have more details about it?

3 of 37 comments (clear)

  1. Full text of the article by mcelrath · · Score: 4
    Is here. (From Science Magazine)

    --Bob

    --
    1^2=1; (-1)^2=1; 1^2=(-1)^2; 1=-1; 1=0.
  2. Quick Overview of Superconductivity by sig · · Score: 5

    Quantum Mechanics allows electrons to fill a finite number of states. Since electrons are fermions, they obey the Pauli exclusion principal: No two electrons can be in the same state at the same time. When you have a lare sample of something (like a copper wire) there are a bunch of states at the top, and most of them are unfilled. Insulators have no empty states, so there is no where for them to go. Conductors have lots of empty states, so they just glide along.

    At superconductor temperatures, the vibrations of the atoms slow way down and the electrons tap in to these low freq vibrational modes (called phonons, but thats not importart) causing a net attraction between electrons. Which is wierd because normally electrons repel each other.

    So then the electrons pair off (into Cooper Pairs, but still not important) but these pairs are no longer fermions. (This is the important part) Instead the pairs behave as Bosons, which don't obey the Pauli exclusion principle.

    All the electron pairs end up in the same lowest energy state. Now when they travel, they all travel together, but they never have to worry about finding an empty state, so they don't loose any energy.

    cya

  3. Interesting idea by Rayban · · Score: 5

    Well, I guess the paper doesn't really explain how this can be useful. The difference between a standard transistor and a transistor I assume that would be made from this is that the logic would be controlled by unrestricted current flow, as opposed to voltage (well, *technically* standard CMOS logic relies on current, but it's essentially voltage based).

    The setup for creating the standard logic gates would be similar to the CMOS version and probably wouldn't take anyone longer than an hour or so to flesh out.

    The advantages:
    - *zero* power loss in the transistors: this means almost zero power consumption in the chip
    - low-to-zero capacitance in the transistors: computers that operate at the speed of light (electrons moving as fast as physically possible)

    I don't know if the switch between conductor/insulator is infitesmal or requires a fairly large time to occur, however. I guess we'll see in a few months.

    Exciting technology.. any more info, anyone?

    --
    æeee!