Ambivalence of the anisotropy of the vortex lattice in an anisotropic type-II superconductor

TL;DR

This paper discusses how vortex lattice configurations in anisotropic type-II superconductors can change due to energy considerations, potentially undergoing a first-order phase transition as the magnetic field varies.

Contribution

It introduces a geometry-based analysis of vortex lattice modifications and predicts a possible first-order phase transition between them in anisotropic superconductors.

Findings

Two distinct vortex lattice modifications are possible.

A first-order phase transition may occur between these modifications.

Conditions for the transition depend on energy considerations and external magnetic field.

Abstract

We present a geometry-based discussion of possible vortex configurations in the mixed state of anisotropic type-II superconductors. It is shown that, if energy considerations assign six nearest neighbors to each vortex, two distinct modifications of the vortex lattice are possible. It is expected that certain conditions lead to a first order phase transition from one modification of the vortex lattice to the other upon varying the external magnetic field.