Is there a Phase Transition to the Flux Lattice State?

TL;DR

This paper proposes that the observed sharp drops in resistance and magnetization in vortex matter are due to a dimensional crossover, not a phase transition, aligning theoretical estimates with experimental data.

Contribution

It challenges the traditional interpretation of a phase transition, offering a crossover explanation based on phase coherence length and sample thickness.

Findings

Resistance and magnetization drops are due to a dimensional crossover.

Estimated crossover width matches experimental observations.

Phase coherence length scales are consistent with the crossover model.

Abstract

The sharp drops in the resistance and magnetization which are usually attributed to a phase transition from the vortex liquid state to a crystal state are explained instead as a crossover between three and two dimensional behavior, which occurs when the phase coherence length in the liquid becomes comparable to the sample thickness. Estimates of the width of the crossover region and the phase coherence length scales are in agreement with experiment.