Nanoscale superconducting properties of amorphous W-based deposits grown with focused-ion-beam

TL;DR

This study uses low-temperature STM/S to analyze amorphous W-based superconducting nanodeposits, revealing homogeneous surface superconductivity and vortex lattice structures, highlighting potential for nanofabrication of superconducting circuits.

Contribution

It demonstrates the homogeneous superconducting properties of amorphous W-based deposits and explores their potential for nanofabrication of superconducting circuits using focused-ion-beam.

Findings

Superconducting gap follows s-wave BCS theory.

Hexagonal vortex lattice observed under magnetic fields.

Surface superconductivity is homogeneous down to atomic scale.

Abstract

We present very low temperature Scanning Tunneling Microscopy and Spectroscopy (STM/S) measurements in W-based amorphous superconducting nanodeposits grown using a metal-organic precursor and focused-ion-beam. The superconducting gap closely follows s-wave BCS theory, and STS images under magnetic fields show a hexagonal vortex lattice whose orientation is related to features observed in the topography through STM. Our results demonstrate that the superconducting properties at the surface of these deposits are very homogeneous, down to atomic scale. This, combined with the huge nanofabrication possibilities of the focused-ion-beam technique, paves the way to use focused-ion-beam to make superconducting circuitry of many different geometries.