Proximity Effect in a Superconductor-Metallofullerene-Superconductor Molecular Junction

TL;DR

This study demonstrates proximity-induced superconductivity in a single Gd metallofullerene molecule junction, highlighting the influence of molecular size and spin states on superconducting transport.

Contribution

It provides experimental evidence of proximity effects at the molecular level and explains the role of molecular size and spin states in superconducting junctions.

Findings

Proximity-induced superconductivity observed in single-molecule junctions.

No proximity effect in larger metallofullerene clusters.

Multiple Andreev reflections and Gd spin states influence superconducting behavior.

Abstract

We report low-temperature transport measurements through molecules of Gd metallofullerenes between superconducting suspended electrodes. The presence and number of molecules in the 2 nm-wide gap between electrodes was determined by high resolution transmission electron microscopy. We find that a junction containing a single metallofullerene dimer between superconducting electrodes displays signs of proximity-induced superconductivity. In contrast, no proximity effects develops in junctions containing larger cluster of metallofulerenes. These results can be understood by taking into account multiple Andreev reflections, and the spin states of the Gd atoms.