Ordered Bose Glass of Vortices in Superconducting YBa$_{2}$Cu$_{3}$O$_{7-\delta}$ Thin Films with a Periodic Pin Lattice Created by Focused Helium Ion Irradiation

TL;DR

This study demonstrates the creation of an ordered Bose glass phase of vortices in YBCO thin films by engineering a periodic array of columnar defects using focused helium ion irradiation, revealing new vortex matter behavior.

Contribution

It introduces a method to induce an ordered Bose glass phase in YBCO films through periodic defect arrays created by focused helium ion beams, advancing vortex matter control.

Findings

Observation of an ordered Bose glass phase of vortices.

Successful engineering of a hexagonal defect lattice with 30 nm spacing.

Identification of vortex arrangements via characteristic scaling behaviors.

Abstract

The defect-rich morphology of YBa$_{2}$Cu$_{3}$O$_{7-\delta}$ (YBCO) thin films leads to a glass-like arrangement of Abrikosov vortices which causes the resistance to disappear in vanishing current densities. This vortex glass consists of entangled vortex lines and is identified by a characteristic scaling of the voltage-current isotherms. Randomly distributed columnar defects stratify the vortex lines and lead to a Bose glass. Here, we report on the observation of an ordered Bose glass in a YBCO thin film with a hexagonal array of columnar defects with 30 nm spacings. The periodic pinning landscape was engineered by a focused beam of 30 keV He$^+$ ions in a helium-ion microscope.