Vortex lattices in strong type-II superconducting two-dimensional strips

TL;DR

This paper presents a semi-analytical method to study vortex lattices in strong type-II superconducting nanostructures, revealing surface effects and energy oscillations with magnetic field.

Contribution

It introduces a novel semi-analytical approach to analyze vortex states in 2D superconducting strips, including surface superconductivity effects.

Findings

Vortex lattice solutions incorporating surface superconductivity.

Energy cost of vortex row displacement oscillates with magnetic field.

Surface vortex shear energy vanishes at a critical magnetic field.

Abstract

We show how to calculate semi-analytically the dense vortex state in strong type-II superconducting nanostructures. For the specific case of a strip, we find vortex lattice solutions which also incorporate surface superconductivity. We calculate the energy cost to displace individual vortex rows parallel to the surfaces and find that this energy oscillates with the magnetic field. Remarkably, we also find that, at a critical field $H^*$ below $H_{c2}$, this ''shear'' energy becomes strictly zero for the surface rows due to an unexpected mismatch with the bulk lattice.