Creating Nanostructured Superconductors On Demand by Local Current Annealing

TL;DR

This paper introduces a novel local current annealing technique using STM to create nanostructured superconducting islands in YPtBi, enabling precise control over their shape and size for potential quantum applications.

Contribution

The study demonstrates a new method for fabricating nanometer-scale superconductors by partial crystallization of YPtBi using local current annealing in STM, advancing nanoscale superconductor engineering.

Findings

Reproducible creation of 100 nm superconducting islands

Characterization of superconducting properties including gap, T_c, and vortex behavior

Potential for tailored nanostructured superconductors in quantum technologies

Abstract

Superconductivity results from a Bose condensate of Cooper-paired electrons with a macroscopic quantum wavefunction. Dramatic effects can occur when the region of the condensate is shaped and confined to the nanometer scale. Recent progress in nanostructured superconductors has revealed a route to topological superconductivity, with possible applications in quantum computing. However, challenges remain in controlling the shape and size of specific superconducting materials. Here, we report a new method to create nanostructured superconductors by partial crystallization of the half-Heusler material, YPtBi. Superconducting islands, with diameters in the range of 100 nm, were reproducibly created by local current annealing of disordered YPtBi in the tunneling junction of a scanning tunneling microscope (STM). We characterize the superconducting island properties by scanning tunneling spectroscopic measurements to determine the gap energy, critical temperature and field, coherence length, and vortex formations. These results show unique properties of a confined superconductor and demonstrate that this new method holds promise to create tailored superconductors for a wide variety of nanometer scale applications.