Evaporation of the pancake-vortex lattice in weakly-coupled layered superconductors

TL;DR

This paper models the melting transition of pancake-vortex lattices in layered superconductors, bridging high-field 2D melting and zero-field evaporation, using a mean-field substrate approach to determine the stability and transition characteristics.

Contribution

It introduces a mean-field substrate model to analyze the melting line of pancake-vortex systems, connecting different regimes and calculating the first-order transition parameters.

Findings

Identifies the thermal stability limit of the 3D vortex solid.

Determines the first-order melting transition and entropy jump.

Interpolates between 2D melting and single-stack evaporation regimes.

Abstract

We calculate the melting line of the pancake-vortex system in a layered superconductor, interpolating between two-dimensional (2D) melting at high fields and the zero-field limit of single-stack evaporation. Long-range interactions between pancake vortices in different layers permit a mean-field approach, the ``substrate model'', where each 2D crystal fluctuates in a substrate potential due to the vortices in other layers. We find the thermal stability limit of the 3D solid, and compare the free energy to a 2D liquid to determine the first-order melting transition and its jump in entropy.