Does the Meissner effect violate the second law of thermodynamics? Comment on "The Law of Entropy Increase and the Meissner Effect" by A. Nikulov

TL;DR

This paper argues that the Meissner effect does not violate the second law of thermodynamics if a mechanism exists for supercurrent dynamics without Joule heat, supported by the hole superconductivity theory.

Contribution

It demonstrates that the Meissner effect aligns with thermodynamics when considering the hole superconductivity mechanism, challenging prior claims of violation.

Findings

The Meissner effect is thermodynamically consistent with a suitable supercurrent mechanism.

The conventional theory of superconductivity does not provide such a mechanism.

Hole carriers in the normal state are essential for this consistency.

Abstract

In Entropy 24, 83 (2022) [1], titled "The Law of Entropy Increase and the Meissner Effect", A. Nikulov claims that the Meissner effect exhibited by type I superconductors violates the second law of thermodynamics. Contrary to this claim, I show that the Meissner effect is consistent with the second law of thermodynamics provided that a mechanism exists for the supercurrent to start and stop without generation of Joule heat. The theory of hole superconductivity provides such a mechanism, the conventional theory of superconductivity does not. It requires the existence of hole carriers in the normal state of the system.