Strongly Enhanced Vortex Pinning by Conformal Crystal Arrays

TL;DR

This paper demonstrates that conformal crystal arrays significantly improve vortex pinning in superconductors, outperforming traditional random or periodic arrangements across a broad range of magnetic fields.

Contribution

It introduces conformal crystal arrays as a novel, highly effective pinning landscape that enhances vortex pinning through structural and gradient matching effects.

Findings

Stronger vortex pinning over larger field ranges with conformal arrays

Matching of flux gradient and pinning gradient enhances pinning

Sixfold order preservation is crucial for pinning effectiveness

Abstract

Conformal crystals are non-uniform structures created by a conformal transformation of regular two-dimensional lattices. We show that gradient-driven vortices interacting with a conformal pinning array exhibit substantially stronger pinning effects over a much larger range of field than found for random or periodic pinning arrangements. The pinning enhancement is partially due to matching of the critical flux gradient with the pinning gradient, but the preservation of the sixfold ordering in the conformally transformed hexagonal lattice plays a crucial role. Our results can be generalized to a wide class of gradient-driven interacting particle systems such as colloids on optical trap arrays.