Phase coherent transport in Kondo/superconducting hybrid structures

TL;DR

This study investigates phase coherent transport in hybrid structures combining Kondo and superconducting materials, revealing proximity effects and phase coherence phenomena influenced by the Kondo effect.

Contribution

It demonstrates the existence of superconducting proximity effects and phase coherence in Kondo AuFe wires, with detailed measurements of magnetoresistance oscillations.

Findings

Superconducting proximity effect extends over ~0.5 μm in Kondo wires.

Aharonov-Bohm oscillations confirm electronic phase coherence.

Reentrant magnetoresistance behavior peaks at ~870 mK due to Kondo-superconductor interplay.

Abstract

We present measurements of the transport properties of hybrid structures consisting of a Kondo AuFe film and a superconducting Al film. The temperature dependence of the resistance indicates the existence of the superconducting proximity effect in the Kondo AuFe wires over the range of $\sim0.5$ $\mu$m. Electronic phase coherence in the Kondo AuFe wires has been confirmed by observing the Aharanov-Bohm effect in the magnetoresistance of the loop structure. The amplitude of the magnetoresistance oscillations shows a reentrant behavior with a maximum at $\sim$ 870 mK, which results from an interplay between the Kondo effect and the superconducting proximity effect.