Weak links in proximity superconducting two dimensional electron systems

TL;DR

This paper reports a giant inverse proximity effect in low-dimensional superconducting devices, where normal conductors significantly suppress superconductivity, differing from standard superconductor-normal-superconductor junctions.

Contribution

It reveals a new inverse proximity effect in 2D electron systems that drastically reduces superconductivity, highlighting a different mechanism from traditional S/N/S junctions.

Findings

Normal conductors induce a strong back-action on superconducting regions.

Superconducting characteristics are suppressed below typical S/N/S levels.

The effect is significant even when normal parts are smaller than the coherence length.

Abstract

We report a giant inverse proximity effect that arises in the low-dimensional devices and is crucially different from proximity in the standard superconductor-normal-superconductor (S/N/S) junctions. The normal conductors induce a giant back-action on the proximity superconducting regions even when the dimensions of the normal parts are smaller than the proximity coherence length. This essentially suppresses the superconducting characteristics of the entire system, including the critical current, well below those for the usual S/N/S structures.