Quantum breakdown of superconductivity in low-dimensional materials

TL;DR

This paper reviews how superconductivity can be destroyed in low-dimensional materials through disorder, localization, and Josephson coupling, highlighting recent experimental and theoretical advances.

Contribution

It provides a comprehensive overview of the mechanisms leading to the breakdown of superconductivity in low-dimensional systems, integrating recent experimental findings and theoretical insights.

Findings

Disorder increases Coulomb repulsion, destroying superconductivity.

Anderson localization causes electronic granularity affecting superconductivity.

Superconducting islands coupled via proximity effect can transition to resistive states.

Abstract

In order to understand the emergence of superconductivity it is useful to study and identify the various pathways leading to the destruction of superconductivity. One way is to use the increase in Coulomb-repulsion due to the increase in disorder, which overpowers the attractive interaction responsible for Cooper-pair formation. A second pathway, applicable to uniformly disordered materials, is the competition between superconductivity and Anderson localization, which leads to electronic granularity in which phase and amplitude fluctuations of the superconducting order parameter play a role. Finally, a third pathway is an array of superconducting islands coupled by some form of proximity-effect, due to Andreev-reflections, and which leads from a superconducting state to a state with finite resistivity, which appears like a metallic groundstate. This review summarizes recent progress in understanding of these different pathways, including experiments in low dimensional materials and application in superconducting quantum devices.