Superconducting proximity effect in a mesoscopic ferromagnetic wire

TL;DR

This paper reports an experimental investigation of how superconductivity influences a ferromagnetic wire's transport properties, revealing a larger-than-expected proximity effect decay length in a Co-Al system.

Contribution

It provides new experimental evidence of the superconducting proximity effect in a ferromagnetic wire, challenging existing theoretical expectations about decay length limitations.

Findings

Proximity effect decay length exceeds theoretical predictions

Resistance depends on temperature and voltage below superconducting transition

Superconductivity significantly alters ferromagnetic wire transport properties

Abstract

We present an experimental study of the transport properties of a ferromagnetic metallic wire (Co) in metallic contact with a superconductor (Al). As the temperature is decreased below the Al superconducting transition, the Co resistance exhibits a significant dependence on both temperature and voltage. The differential resistance data show that the decay length for the proximity effect is much larger than we would simply expect from the exchange field of the ferromagnet.