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Anomalous hall effect in the (in,mn)sb dilute magnetic semiconductor
G Mihály1, M Csontos, S Bordács
1Department of Physics, Budapest University of Technology and Economics, and Condensed Matter Research Group of the Hungarian Academy of Sciences, 1111 Budapest, Hungary.
Physical Review Letters
|March 21, 2008
Summary
The anomalous Hall effect in ferromagnetic (In,Mn)Sb is intrinsic, not directly tied to magnetization. Pressure affects scattering but not the Hall effect, supporting Berry phase theory for (III,Mn)V semiconductors.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Semiconductor Physics
Background:
- The anomalous Hall effect (AHE) in magnetic semiconductors is crucial for spintronic applications.
- Understanding the origins of AHE in (III,Mn)V materials like (In,Mn)Sb is key to their technological development.
Purpose of the Study:
- To investigate the anomalous Hall resistivity in ferromagnetic (In,Mn)Sb under high magnetic fields and pressure.
- To elucidate the relationship between AHE, magnetization, and electronic band structure.
- To determine if AHE in this material is an intrinsic property.
Main Methods:
- High magnetic field measurements of Hall resistivity in (In,Mn)Sb.
- Application of hydrostatic pressure to study its influence on the Hall effect.
- Separation of normal and anomalous Hall contributions.
Main Results:
- The anomalous Hall term in (In,Mn)Sb is not proportional to magnetization and can change sign with magnetic field.
- Hydrostatic pressure alters scattering mechanisms but does not affect the Hall effect.
- These findings indicate that the AHE in (In,Mn)Sb is an intrinsic property.
Conclusions:
- The observed behavior supports the Berry phase theory for (III,Mn)V semiconductors.
- A phenomenological model is proposed, linking AHE to field-dependent shifts in valence bands (heavy-hole, light-hole, and split-off bands).
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