Stability conditions for mean-field limiting vorticities of the Ginzburg-Landau equations in 2D

TL;DR

This paper investigates the stability conditions of limiting vorticities in the Ginzburg-Landau equations as the parameter tends to zero, revealing how geometric factors influence stability in the presence or absence of magnetic fields.

Contribution

It provides a rigorous analysis of the limiting stability conditions for vorticities in the Ginzburg-Landau model, including examples and conditions for stability depending on domain size.

Findings

Vorticity stability depends on domain size in magnetic field cases.

Without magnetic field, all critical measures satisfy second order stability.

Established convergence of quadratic energy terms involving weak derivatives.

Abstract

We analyse the limit of stable solutions to the Ginzburg-Landau (GL) equations when $\varepsilon$, the inverse of the GL parameter, goes to zero and in a regime where the applied magnetic field is of order $|\log \varepsilon |$ whereas the total energy is of order $|\log \varepsilon|^2$. In order to do that we pass to the limit in the second inner variation of the GL energy. The main difficulty is to understand the convergence of quadratic terms involving derivatives of functions converging only weakly in $H^1$. We use an assumption of convergence of energies, the limiting criticality conditions obtained by Sandier-Serfaty by passing to the limit in the first inner variation and properties of limiting vorticities to find the limit of all the desired quadratic terms. At last we investigate the limiting stability condition we have obtained. In the case with magnetic field we study an example of an admissible limiting vorticity supported on a line in a square $\Omega=(-L,L)^2$ and show that if $L$ is small enough this vorticiy satisfies the limiting stability condition whereas when $L$ is large enough it stops verifying that condition. In the case without magnetic field we use a result of Iwaniec-Onninen to prove that every measure in $H^{-1}(\Omega)$ satisfying the first order limiting criticality condition also verifies the second order limiting stability condition.