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I have done some reading on superconductance and understand that the reason it happens is due to the formation of Cooper pairs resulting from the attractive momentary charge concentration resulting from a phonon. (As a side-question, is that very different from London dispersion force or a temporary dipole in essence?)

What I don't understand is why an electron would cause a phonon to be produced resulting in a Cooper pair at 4 Kelvin but that same election wouldn't at 273 K.

Is this because Cooper pairs have relatively weak bonds? Is it just really energetically unfavorable to have these two electrons hanging out in a net-zero spin state? Does nature abhor electrons violating the Pauli exclusion principle?

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So upon looking into this further, it looks like Cooper pair interactions are pretty weak, on the order of 10^-3 eV. As such, I'm guessing the reason that we see superconducting at low temps and not at higher temps (with a few "hot superconductors" making an exception) is because at higher temperatures there is enough energy in the system such that Cooper pair interactions would last only momentarily such that you wouldn't have all of the electrons flowing in the conductor taking on a Cooper pair formation simultaneously to allow resistance-free conductance.

I feel that's a sufficient answer and this question can be closed.

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  • $\begingroup$ You completely miss the important point that superconductivity is due to a macroscopic quantum condensate. Then you question is completely ill defined : temperature is a problem of statistical physics, not of the binding energy of two electrons taken alone. Temperature can not be defined for one or two electrons as you suggest in your question and answer. The balance would be roughly between the binding energy and the thermal excitation, though this is again pretty inconsistent because superconductivity is a transmutation of fermions to bound state bosons. $\endgroup$ – FraSchelle Apr 11 '16 at 13:15

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