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Optimized Setup and Protocol for Magnetic Domain Imaging with In Situ Hysteresis Measurement
Published on: November 7, 2017
Dipolar-energy-activated magnetic domain pattern transformation driven by thermal fluctuations
M Kronseder1, M Buchner, H G Bauer
1Physics Department, Universität Regensburg, Universitätsstrasse 31, Regensburg, Germany. matthias.kronseder@ur.de
Nature Communications
|June 21, 2013
Summary
Investigating ultra-thin ferromagnetic films revealed a surprising metastable magnetic domain state. This state, with wider domains than expected, transforms into the stable phase through a propagating transition front.
Area of Science:
- Condensed matter physics
- Materials science
- Surface science
Background:
- Two-dimensional (2D) ferromagnetic layers offer tunable magnetic properties for studying pattern formation.
- Understanding magnetic domain structures is crucial for spintronic applications and fundamental physics.
Purpose of the Study:
- To investigate the magnetic domain behavior of ultra-thin Fe/Ni/Cu(001) films near the spin reorientation transition.
- To explore the influence of film thickness, temperature, and effective anisotropy on domain formation.
- To characterize a metastable domain state and its transformation dynamics.
Main Methods:
- Utilized threshold photoemission magnetic circular dichroism (XMCD) for magnetic contrast.
- Employed photoemission electron microscopy (PEEM) for high-resolution imaging of domain structures.
- Systematically varied film thickness, temperature, and effective anisotropy.
Main Results:
- Observed a metastable magnetic domain state with a larger domain width than the thermodynamically stable state.
- Identified that this metastable state arises from a rapid reduction in effective anisotropy.
- Demonstrated that the transformation to the equilibrium state occurs via a transition front propagation.
- Found that the transition front originates from defined steps in film thickness.
Conclusions:
- Ultra-thin ferromagnetic films can exhibit metastable magnetic domain configurations.
- Anisotropy reduction is a key factor in accessing these metastable states.
- The dynamics of domain transformation are governed by transition front propagation, influenced by film thickness variations.
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