On the theoretical RF field limits of multilayer coating structures of superconducting resonator cavities

TL;DR

This paper defends the theoretical limits of multilayer superconducting coatings in RF cavities, countering previous criticisms and reaffirming their potential to reduce vortex dissipation.

Contribution

It provides a theoretical rebuttal to prior criticisms of the SIS multilayer approach for superconducting RF cavities.

Findings

Criticism of SIS multilayer approach is unsubstantiated

Reaffirms the potential of multilayer coatings to reduce vortex dissipation

Supports the validity of existing theoretical limits

Abstract

This Comment addresses theoretical field limits for superconducting-insulating (S-I) thin films multilayers discussed by S. Posen, G. Catelani, M. Liepe, J. Sethna, and M. Transtrum [1]. It is shown that their criticism of the SIS multilayer approach [2] to reduce vortex dissipation in superconducting RF resonator cavities is unsubstantiated