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

Abstract

We comment on a recent letter by Schopohl and Dolgov (SD) which raised the possibility that a d-wave superconductor might be thermodynamically unstable in the limit $T\to 0$. The point of our comment is that this instability can be inevitably prevented by the non-local effects.

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