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Optimized Setup and Protocol for Magnetic Domain Imaging with In Situ Hysteresis Measurement
Published on: November 7, 2017
Experimental observation of disorder-driven hysteresis-loop criticality
A Berger1, A Inomata, J S Jiang
1Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439, USA.
Physical Review Letters
|November 1, 2000
Summary
We explored how magnetic disorder affects magnetization reversal in Co/CoO films. Temperature changes revealed a critical point, altering reversal from smooth to discontinuous, indicating a disorder-driven phase transition.
Area of Science:
- Condensed Matter Physics
- Materials Science
Background:
- Magnetization reversal is crucial for magnetic storage devices.
- Understanding magnetic disorder effects is key to controlling material properties.
Purpose of the Study:
- To investigate the influence of magnetic disorder on magnetization reversal in Co/CoO thin films.
- To identify and characterize a disorder-driven critical point.
Main Methods:
- Utilized thin Co/CoO films with an antiferromagnetic CoO layer.
- Varied temperature to tune magnetic disorder and observe magnetization reversal.
- Analyzed magnetization loops and scaling behavior near the critical point.
Main Results:
- Discontinuous magnetization reversal observed above a critical temperature (T(c)).
- Smooth magnetization loops observed below T(c).
- Established a disorder-driven critical point in the nonequilibrium phase diagram.
- Observed scaling behavior and determined critical exponents beta = 0.022+/-0.006 and betadelta = 0.30+/-0.03.
Conclusions:
- Magnetic disorder significantly impacts magnetization reversal.
- A critical point exists, driven by disorder, influencing the magnetic phase diagram.
- The system exhibits scaling behavior, providing insights into critical phenomena in two-dimensional magnetic systems.
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