"Heat Transport as Probe of Superconducting Gap Structure"

This paper by Shakeripour, Petrovic and Taillefer is a good resource for understanding thermal conductivity data for a superconductor.
The paper gives examples and brief explanations for the temperature and magnetic field dependence of thermal conductivity of fully gapped and nodal superconductors.

The paper is divided into four sections and a summary, but for now I will only outline the first 2:

Residual heat conduction as T-> 0
- k generally has 2 terms: linear and cubic. Linear term represents conduction due to thermally activated quasi-particled (e.g. electrons).
- For s-wave SC: k/T -> 0 for T->0 (since thermally activated quasi-particle, TAQP, d.o.s. should go to zero for fully gapped SC)
- For nodal SC: there are residual TAQP d.o.s. at T->0 that are protected by symmetry against disorder and therefore conduct heat
- see figure 1 of [1]
Magnetic Field Dependence
- For s-wave SC: TAQP are located in vortex core, therefore only conduction by tunneling => exponential with field (positive concavity)
- For nodal SC: Conduction is dominated by TAQP outside vortex core (at stated near node) with 2 field dependent processes:
  - Doppler shift caused by field-induced superfluid flow results in shift in low-energy d.o.s. proportional to B^1/2 (this effect dominates at low fields)
  - Zeeman effect results in shift in low-energy d.o.s. proportional to B (dominates at high fields)
- see figure 2 of [1]

Linked Notes:
Field Dependence of Thermal Conductivity
Residual Heat Conduction as T -> 0

Tags:
Thermal Conductivity

References:
[1] H. Shakeripour, C Petrovic and Louis Taillefer NJP (2009) "Heat Transport as Probe of Superconducting Gap Structure"