Quasi-athermal domain-wall dynamics
The demagnetising field may stabilise in-plane domain walls and suppress thermally activated creep at room temperature.
Awarded project · 2026–2029
DYNAMAG
Domain Walls Dynamics in Planar Anisotropic Ferromagnets
Continuity with ARTIFAQS
DYNAMAG continues and extends the programme initiated by ARTIFAQS, which remains active during 2023–2026. The new stage will start on 1 September 2026.
Scientific objective
DYNAMAG investigates the dynamics of domain walls in ferromagnetic thin films with in-plane magnetic anisotropy. It aims to uncover the mechanisms that suppress or stabilise creep at room temperature and to control transitions between creep, avalanche, depinning and flow regimes.
The project introduces static and dynamically tunable disorder as a control parameter. Surface acoustic waves will modulate the magnetic energy landscape through magnetoelastic coupling, providing reversible spatio-temporal disorder within the same device.
Starting hypotheses
Tunable anisotropic disorder
Geometry, local anisotropy and field orientation can move the system between different avalanche and flow regimes.
Dynamic disorder generated by SAWs
Periodic magnetoelastic perturbations can synchronise avalanches and modify criticality in real time.
Spatio-temporal avalanche correlations
Aftershock-like triggering, pseudogaps and multimodal interactions will be analysed using point-process and branching models.
Methods
- Growth of Ni, Co, permalloy and Fe thin films by evaporation and RF/DC sputtering.
- Real-time MOKE imaging under quasi-static and pulsed magnetic fields.
- SAW devices with interdigitated transducers and magnetic layers on piezoelectric substrates.
- Magnetoresistance and ferromagnetic-resonance characterization.
- Automated image processing and sub-pixel domain-wall tracking.
- MuMax3 simulations, interface-depinning models and statistical point-process analysis.
Work packages
WP1Sample preparation and characterization
Geometry, static disorder, anisotropy and SAW devices.
WP2Avalanche regimes under quasi-static fields
MOKE imaging, avalanche statistics and image processing.
WP3Domain-wall velocity under pulsed fields
Creep, depinning and flow maps under static and dynamic disorder.
WP4Spatio-temporal avalanche correlations
Regularity, clustering, aftershocks and theoretical modelling.
WP5Management, open science and dissemination
Publications, data management, conferences and outreach.
Expected impact
The project will provide a controlled experimental platform for non-equilibrium criticality and may establish physical principles for multilevel domain-wall devices, memristive concepts and neuromorphic hardware. It will also develop statistical tools relevant to avalanche phenomena beyond magnetism.