A New Experimental Method for Determining the Pinning Energy of an Abrikosov Vortex

TL;DR

This paper introduces a new experimental method to accurately measure the pinning energy of Abrikosov vortices in high-temperature superconductors, addressing previous measurement discrepancies and aiding in device design.

Contribution

The study presents a novel experimental approach based on a theoretical framework to determine vortex pinning energy, validated with BaZrO$_3$-nanocolumns in YBCO, applicable to various materials.

Findings

Estimated pinning energy of 0.04 eV/nm for BaZrO$_3$-nanocolumns

Discrepancy with previous magnetic relaxation measurements explained

Method reduces ambiguity in vortex pinning energy measurement

Abstract

We demonstrate a novel method of experimentally addressing the pinning energy of an Abrikosov vortex in high-temperature superconducting thin films. The method is based on our previously published theoretical framework considering the optimization of heterostructural bilayer films. To demonstrate our method, we have estimated the pinning energy of a typical BaZrO$_3$-nanocolumn within YBa$_2$Cu$_3$O$_{6+x}$ lattice using the experimental data from our previous study. Our calculations result in pinning energy of 0.04 eV/nm for a $c$-axis oriented vortex, which is in excellent agreement with a widely used theoretical formula for artificial columnar defects. However, the estimated energy is significantly higher than what has been previously reported for BaZrO$_3$-nanocolumns based on magnetic relaxation measurements. We argue that this discrepancy originates from the previously raised issues concerning the reliability of the magnetic relaxation measurements in determining the pinning energy. While the presented study only considers BaZrO$_3$-nanocolumns in YBa$_2$Cu$_3$O$_{6+x}$, the demonstrated method is equally applicable to any pinning site and superconducting material. The introduced method of measuring the pinning energy of Abrikosov vortices reduces the present ambiguity around the topic and enables more reliable modeling and design of YBCO based cryogenic memory cells and investigation for their use in quantum applications.