Melting of the vortex lattice in high $T_{c}$ superconductors

TL;DR

This paper develops a precise Ginzburg-Landau theoretical model to describe vortex lattice melting in high-temperature superconductors, matching experimental magnetization and specific heat data.

Contribution

It introduces a high-precision theoretical framework for vortex melting, accurately predicting magnetization and specific heat jumps in high $T_c$ superconductors.

Findings

Magnetization in the liquid phase exceeds that in the solid by 1.8%.

Specific heat jump at melting is about 6% and decreases with temperature.

Theoretical results align with experimental data on YBCO and Monte Carlo simulations.

Abstract

The precise measurements of vortex melting point towards a need to develop a quantitative theoretical description of thermal fluctuations in vortex matter. To tackle the difficult problem of melting, the description of both the solid and the liquid phase should reach the precision level well below 0.1%. Such a theory in the framework of the Ginzburg - Landau approach is presented. The melting line location is determined and magnetization, specific heat jumps along it are calculated. We find that the magnetization in the liquid is larger than that in the solid by 1.8% regardless of the melting temperature, while the specific heat jump is about 6% and slowly decreases with temperature. The magnetization curves agree with experimental results on $YBCO$ and Monte Carlo simulations.