High-Tc Superconductors in Applied Magnetic Fields Parallel to the CuO Planes: First Order Transition with Slow Onset of Resistivity

TL;DR

This study uses Monte Carlo simulations of a 3D XY model to investigate the phase transition in high-Tc superconductors under magnetic fields parallel to CuO planes, revealing a first order transition and explaining experimental resistivity behavior.

Contribution

It provides the first simulation evidence of a first order transition in this context and discusses the impact of vortex line barriers on resistivity onset.

Findings

Evidence for a first order transition in the model.

Large potential barriers cause slow resistivity onset.

Alignment of magnetic field affects vortex dynamics.

Abstract

The three dimensional uniformly frustrated XY model is used as a model of a high temperature superconductor in an applied magnetic field parallel to the CuO-planes. Through Monte Carlo simulations with anisotropy $\eta^2 = 10$ on large lattices we find evidence for a first order transition. Earlier simulations and theoretical treatments are discussed and the experimentally found smooth onset of resistivity is suggested to be due to a large potential barrier against vortex line motion above $T_c$ present for perfect alignment of the applied field.