Comment on "T-dependence of the magnetic penetration depth in unconventional superconductors at low temperatures: Can it be linear?"

TL;DR

This paper clarifies that clean superconductors with line gap nodes are consistent with the Nernst theorem, affirming the possibility of linear T-dependence of the magnetic penetration depth at low temperatures.

Contribution

It provides a theoretical clarification resolving previous conflicts regarding the T-dependence of penetration depth in nodal superconductors.

Findings

Superconductors with line gap nodes are compatible with the Nernst theorem.

The T-dependence of the magnetic penetration depth can be linear at low temperatures.

The paper confirms the answer to the debated question is yes.

Abstract

We show that the clean superconductor with line of gap nodes is not in conflict with the Nernst theorem. The answer to the question in the title of the Schopohl-Dolgov paper in Phys. Rev. Lett. 80 (1998) 4761 (cond-mat/9802264) is yes.