Please explain "Exponential behavior usually signals the presence of a gap in the energy spectrum" How The presence of a gap explains the exponential decrease of the specific heat and the thermal conductivity below TC.

  • $\begingroup$ Please give a reference. $\endgroup$
    – my2cts
    Commented Aug 30, 2019 at 18:53

1 Answer 1


At low temperature number of excited electrons above the gap will be proportional to $\exp\{-\Delta/kT\}$ where $\Delta$ is the gap. This decreases very rapidly as $T$ becomes small so will be far fewer excitation than without the gap. Consequently the electronic contribution to the specific heat will be $\exp\{-\Delta/kT\}$ smaller. Gapless superconductors, on the other hand, have specific heats that go to zero as $T^a$ for some power $a$ that depends on the dimension (line or point) of the gapless region on the Fermi surface.


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.