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  1. Standard member sonhouse
    Fast and Curious
    17 Jun '14 13:13
    http://phys.org/news/2014-06-superconducting-secrets-years.html

    Getting closer to understanding the route to room temperature superconductors.
  2. 17 Jun '14 15:59 / 1 edit
    This is fantastic news!
    It is interesting how the worked it out by "working backwards".

    So now we know that something called "charge density waves" is apparently what creates high temperature superconductivity -I have never heard of them!
    and these "charge density waves" cause superconductivity by causing "... 'twisted 'pockets' of electrons in these materials, from which superconductivity emerges....".

    I looked up http://en.wikipedia.org/wiki/Charge_density_wave -I don't pretend to understand it but, just like many concepts in quantum mechanics, this will be something I will now study so that I will at least half understand it.
  3. Standard member sonhouse
    Fast and Curious
    17 Jun '14 16:57 / 3 edits
    Originally posted by humy
    This is fantastic news!
    It is interesting how the worked it out by "working backwards".

    So now we know that something called "charge density waves" is apparently what creates high temperature superconductivity -I have never heard of them!
    and these "charge density waves" cause superconductivity by causing "... 'twisted 'pockets' of electrons in these mat ...[text shortened]... m mechanics, this will be something I will now study so that I will at least half understand it.
    Yeah, same here. Room temperature superconductivity will be useful in so many ways we don't even know all the apps for it yet. One I think about is superconductive plasma shields for incoming spacecraft, if you have a powerful magnetic field in front of an incoming craft it could deflect the hot plasma around the craft and so there would be no need for those huge insulating bricks like on the space shuttle.

    I also wonder what a superconducting antenna would be like for communications and radio telescopes.

    If you look at the little formula for Q of a circuit, reactence over resistance, the lower the resistance, the higher the Q so a superconductive antenna or tuned circuit should have very high Q, which would be extremely useful for radio telescopes since they look at wavelengths of less than one Hertz.

    I wonder what a parabolic reflector would be like if it was a superconductor, would the reflection be better than a conventional reflector, like in radio telescopes or satellite dishes?

    For a resonant circuit, both the capacitive part and the inductive part would need to be superconductive before you would get what I hope would be a large increase in the Q of that circuit.

    I don't know if studies like that have ever been done.

    I actually tried to set up such an experiment with high temp superconductive wire, I figured I could make an antenna and such with polyflow lines running LN2 and keep the superconductor cold and I approached American Superconductor company with that idea, asked them if they could sell me some wire. SELL me some, mind you, not asking for handouts, but they refused, telling me it wasn't an interesting enough project. The asssholes!
  4. 17 Jun '14 19:26 / 8 edits
    Originally posted by sonhouse
    Yeah, same here. Room temperature superconductivity will be useful in so many ways we don't even know all the apps for it yet. One I think about is superconductive plasma shields for incoming spacecraft, if you have a powerful magnetic field in front of an incoming craft it could deflect the hot plasma around the craft and so there would be no need for thos ...[text shortened]... r handouts, but they refused, telling me it wasn't an interesting enough project. The asssholes!
    The 6 significant applications that I am aware of for room temperature superconductors would be:

    1, electric motors and electric generators that are almost 100% energy efficient and which weigh only a tiny fraction of the weight of conventional ones (this is because a superconducting electromagnet requires no heavy core and that would saves considerably on weight) .

    2, much cheaper MRI machines that could be so cheap that even third world hospitals should be able to afford them.

    3, superconducting cables and transformers that waste no energy and would enable a cost effective world wide super grid for efficient transmission of electric power over vast distances.

    4, when combined with spintronics (and I have recently learned that there is a way of combining superconductivity with spintronics so that superconductivity enhances the spintronic effect ) in microchips, microchips that are many times faster and are much more than 10,000 times more energy efficient than conventional microchips and thus use virtually no electricity!

    5, much more cost effective, faster and more energy efficient magnetic levitating trains (which are currently very expensive! )

    6, much better light sensors at the back of cameras that don't need expensive cumbersome cooling and are so light sensitive that would absorb and detect nearly every photon in dim light and which can measure the exact wavelength of every single photon detected (there is a special kind of superconducting light sensor being researched that can do that -just not currently at room temperature ) This could be especially useful for astronomy.

    Anyone like to add to that above list?
  5. 17 Jun '14 20:31
    I have to point out that when it comes to astronomy, the instruments are often kept quite cool anyway. Certainly infrared astronomy requires very cold detectors. Also, if there was a place for superconductors, you would think they would have built it even with the ones available today. Considering the cost of large telescopes, any improvement from super conductors would be worth spending some money on.
    Of course for radio the antennas are just so enormous that cooling them is out of the question, so I guess my comments don't apply there.
  6. Standard member DeepThought
    Losing the Thread
    17 Jun '14 22:27
    Originally posted by humy
    This is fantastic news!
    It is interesting how the worked it out by "working backwards".

    So now we know that something called "charge density waves" is apparently what creates high temperature superconductivity -I have never heard of them!
    and these "charge density waves" cause superconductivity by causing "... 'twisted 'pockets' of electrons in these mat ...[text shortened]... m mechanics, this will be something I will now study so that I will at least half understand it.
    I know virtually nothing about this, but the stuff about twisted pockets of electrons probably refers to homotopy groups (c.f. magnetic monopoles and instantons) and refers to topological effects.