Depinning free of the elastic approximation

We model the isotropic depinning transition of a domain wall using a two-dimensional Ginzburg-Landau scalar field instead of a directed elastic string in a random media. An exact algorithm accurately targets both the critical depinning field and the critical configuration for each sample. For random...

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Detalles Bibliográficos
Autores: Kolton, Alejandro Benedykt, Ferrero, Eduardo Ezequiel, Rosso, Alberto
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2023
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/228525
Acceso en línea:http://hdl.handle.net/11336/228525
Access Level:acceso abierto
Palabra clave:DEPINNING
MAGNETIC DOMAIN WALL
GINZBURG-LANDAU
https://purl.org/becyt/ford/1.3
https://purl.org/becyt/ford/1
Descripción
Sumario:We model the isotropic depinning transition of a domain wall using a two-dimensional Ginzburg-Landau scalar field instead of a directed elastic string in a random media. An exact algorithm accurately targets both the critical depinning field and the critical configuration for each sample. For random bond disorder of weak strength Δ, the critical field scales as Δ4/3 in agreement with the predictions for the quenched Edwards-Wilkinson elastic model. However, critical configurations display overhangs beyond a characteristic length l0∼Δ-α, with α≈2.2, indicating a finite-size crossover. At large scales, overhangs recover the orientational symmetry which is broken by directed elastic interfaces. We obtain quenched Edwards-Wilkinson exponents below l0 and invasion percolation depinning exponents above l0. A full picture of domain-wall isotropic depinning in two dimensions is hence proposed.