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Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Weak-localization correction to the anomalous Hall effect in polycrystalline fe films
1Department of Physics, University of Florida, Gainesville, Florida 32611, USA.
Physical Review Letters
|August 7, 2007
Summary
Researchers studied ultrathin iron films, discovering a universal weak-localization correction explains the anomalous Hall conductivity
Area of Science:
- Condensed matter physics
- Materials science
- Thin film physics
Background:
- Ultrathin films exhibit unique electronic properties.
- Understanding transport phenomena in disordered systems is crucial.
Purpose of the Study:
- Investigate transport properties of ultrathin polycrystalline iron films.
- Determine the origin of anomalous Hall conductivity.
- Analyze the effect of disorder and granularity on transport.
Main Methods:
- In situ transport measurements.
- Variable temperature and magnetic field studies.
- Analysis of sheet resistance and conductivity.
Main Results:
- Logarithmic temperature dependence of anomalous Hall conductivity (sigmaxy) for sheet resistances below 3kΩ.
- Identification of a universal, scale-dependent weak-localization correction within the skew-scattering model.
- Breakdown of universal behavior at higher sheet resistances due to granularity.
- Disorder-dependent decrease in prefactors of lnT correction terms for sigmaxx and sigmaxy.
Conclusions:
- Weak-localization corrections are key to understanding anomalous Hall conductivity in disordered ultrathin films.
- Granularity significantly alters transport properties in highly disordered films.
- Disorder strength dictates the deviation from universal transport behavior.
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