Deterministic roughening in the dc-driven precessional regime of domain walls

Fuente: arXiv
Gespeichert in:
Bibliographische Detailangaben
Hauptverfasser: Pusiol, E. F., Lecomte, V., Bustingorry, S., Kolton, A. B.
Format: Preprint
Veröffentlicht: 2025
Schlagworte:
Online-Zugang:
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
_version_ 1866908827103789056
author Pusiol, E. F.
Lecomte, V.
Bustingorry, S.
Kolton, A. B.
author_facet Pusiol, E. F.
Lecomte, V.
Bustingorry, S.
Kolton, A. B.
contents We numerically study the dynamics of extended domain walls in homogeneous ferromagnets driven by a uniform magnetic field at zero temperature. Using both micromagnetic Landau-Lifshitz-Gilbert simulations and a collective-coordinate description, we show that flat chiral domain walls become linearly unstable above the Walker breakdown field and below a higher threshold, provided their length exceeds a characteristic scale. This instability is captured by a quasi-universal spectral stability diagram, parameterized solely by the Gilbert damping, which predicts the onset of deviations from rigid-wall behavior. Beyond the linear regime, large domain walls with bands of unstable modes develop spatiotemporal chaos, intricate Bloch-line dynamics, and deterministic roughening. At a critical field, the system undergoes a dynamical phase transition from a flat to a rough moving phase with universal features. Our results provide a framework for addressing domain-wall dynamics in the presence of thermal fluctuations and quenched disorder by disentangling their effects from intrinsic deterministic instabilities.
format Preprint
id arxiv_https___arxiv_org_abs_2508_10859
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Deterministic roughening in the dc-driven precessional regime of domain walls
Pusiol, E. F.
Lecomte, V.
Bustingorry, S.
Kolton, A. B.
Disordered Systems and Neural Networks
We numerically study the dynamics of extended domain walls in homogeneous ferromagnets driven by a uniform magnetic field at zero temperature. Using both micromagnetic Landau-Lifshitz-Gilbert simulations and a collective-coordinate description, we show that flat chiral domain walls become linearly unstable above the Walker breakdown field and below a higher threshold, provided their length exceeds a characteristic scale. This instability is captured by a quasi-universal spectral stability diagram, parameterized solely by the Gilbert damping, which predicts the onset of deviations from rigid-wall behavior. Beyond the linear regime, large domain walls with bands of unstable modes develop spatiotemporal chaos, intricate Bloch-line dynamics, and deterministic roughening. At a critical field, the system undergoes a dynamical phase transition from a flat to a rough moving phase with universal features. Our results provide a framework for addressing domain-wall dynamics in the presence of thermal fluctuations and quenched disorder by disentangling their effects from intrinsic deterministic instabilities.
title Deterministic roughening in the dc-driven precessional regime of domain walls
topic Disordered Systems and Neural Networks
url https://arxiv.org/abs/2508.10859