Langevin Simulation of Nonlocal Ginzburg-Landau Model for Superconductors in a Magnetic Field

TL;DR

This paper uses Langevin dynamics to numerically study a nonlocal Ginzburg-Landau model for 2D superconductors in magnetic fields, revealing vortex lattice structures, phase transitions, and thermodynamic properties.

Contribution

It introduces a numerical Langevin simulation approach to analyze nonlocal Ginzburg-Landau models, providing insights into vortex lattice formation and melting in superconductors.

Findings

Vortex lattice close to square symmetry

Identification of vortex lattice melting via specific heat cusp

Calculation of structure factor and Abrikosov factor at various temperatures

Abstract

We numerically investigate the phenomenological nonlocal Ginzburg-Landau Hamiltonian for two-dimensional superconductors in a strong magnetic field by Langevin equation. We obtain a regular vortex lattice which is very near to the square lattice. We calculate the structure factor and Abrikosov factor at various temperatures. We also evaluate the specific heat and obtain a cusp which indicates the melting of the vortex lattice.