Metastability and dynamics of discrete topological singularities in two dimensions: a Γ-convergence approach

R Alicandro, L De Luca, A Garroni… - Archive for Rational …, 2014 - Springer
This paper aims at building a variational approach to the dynamics of discrete topological
singularities in two dimensions, based on Γ-convergence. We consider discrete systems …

Nonlocal-interaction vortices

M Solci - SIAM Journal on Mathematical Analysis, 2024 - SIAM
We consider sequences of quadratic nonlocal functionals, depending on a small parameter,
that approximate the Dirichlet integral by a well-known result by Bourgain, Brezis, and …

Variational equivalence between Ginzburg-Landau, XY spin systems and screw dislocations energies

R Alicandro, M Cicalese, M Ponsiglione - Indiana University Mathematics …, 2011 - JSTOR
We introduce and discuss discrete two-dimensional models for XY spin systems and screw
dislocations in crystals. We prove that, as the lattice spacing ε tends to zero, the relevant …

Domain formation in magnetic polymer composites: an approach via stochastic homogenization

R Alicandro, M Cicalese, M Ruf - Archive for Rational Mechanics and …, 2015 - Springer
We study the magnetic energy of magnetic polymer composite materials as the average
distance between magnetic particles vanishes. We model the position of these particles in …

Existence and stability of a screw dislocation under anti-plane deformation

T Hudson, C Ortner - Archive for Rational Mechanics and Analysis, 2014 - Springer
We formulate a variational model for a geometrically necessary screw dislocation in an anti-
plane lattice model at zero temperature. Invariance of the energy functional under lattice …

Defects in nematic shells: a Γ-convergence discrete-to-continuum approach

G Canevari, A Segatti - Archive for Rational Mechanics and Analysis, 2018 - Springer
In this paper we rigorously investigate the emergence of defects on Nematic Shells with a
genus different from one. This phenomenon is related to a non-trivial interplay between the …

Topological singularities in periodic media: Ginzburg–Landau and core-radius approaches

R Alicandro, A Braides, M Cicalese, L De Luca… - Archive for Rational …, 2022 - Springer
We describe the emergence of topological singularities in periodic media within the
Ginzburg–Landau model and the core-radius approach. The energy functionals of both …

Variational analysis of a two-dimensional frustrated spin system: emergence and rigidity of chirality transitions

M Cicalese, M Forster, G Orlando - SIAM Journal on Mathematical Analysis, 2019 - SIAM
We study the discrete-to-continuum variational limit of the J_1-J_3 spin model on the square
lattice in the vicinity of the ferromagnet/helimagnet transition point as the lattice spacing …

Clearing-out of dipoles for minimisers of 2-dimensional discrete energies with topological singularities

A Garroni, M Petrache, E Spadaro - arXiv preprint arXiv:2408.02136, 2024 - arxiv.org
A key question in the analysis of discrete models for material defects, such as vortices in
spin systems and superconductors or isolated dislocations in metals, is whether information …

The antiferromagnetic XY model on the triangular lattice: topological singularities

A Bach, M Cicalese, L Kreutz, G Orlando - arXiv preprint arXiv:2011.10445, 2020 - arxiv.org
We study the discrete-to-continuum variational limit of the antiferromagnetic XY model on the
two-dimensional triangular lattice in the vortex regime. Within this regime, the spin system …