Effect of hexagonal patterned arrays and defect geometry on the critical current of superconducting films

I. A. Sadovskyy; Y. L. Wang; Z. -L. Xiao; W. -K. Kwok; A. Glatz

doi:10.1103/physrevb.95.075303

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arXiv · 1610.09040

Effect of hexagonal patterned arrays and defect geometry on the critical current of superconducting films

I. A. Sadovskyy·Y. L. Wang·Z. -L. Xiao·W. -K. Kwok·A. Glatz

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Abstract

Understanding the effect of pinning on the vortex dynamics in superconductors is a key factor towards controlling critical current values. Large-scale simulations of vortex dynamics can provide a rational approach to achieve this goal. Here, we use the time-dependent Ginzburg-Landau equations to study thin superconducting films with artificially created pinning centers arranged periodically in hexagonal lattices. We calculate the critical current density for various geometries of the pinning centers --- varying their size, strength, and density. Furthermore, we shed light upon the influence of pattern distortion on the magnetic-field-dependent critical current. We compare our result directly with available experimental measurements on patterned molybdenum-germanium films, obtaining good agreement. Our results give important systematic insights into the mechanisms of pinning in these artificial pinning landscapes and open a path for tailoring superconducting films with desired critical current behavior.

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I. A. Sadovskyy, Y. L. Wang, Z. -L. Xiao, W. -K. Kwok, A. Glatz. 2017-02-01. Effect of hexagonal patterned arrays and defect geometry on the critical current of superconducting films. https://doi.org/10.1103/physrevb.95.075303

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