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Anomalous Hall effect in a two dimensional electron gas with magnetic impurities
Tamara S Nunner1, Gergely Zaránd, Felix von Oppen
1Institut für Theoretische Physik, Freie Universität Berlin, Berlin, Germany.
Physical Review Letters
|July 23, 2008
Summary
We investigated the anomalous Hall effect in 2D electron systems with magnetic impurities and Rashba spin-orbit coupling. The Hall conductivity shows nonlinear dependence on impurity polarization, with potential for resonant enhancement near spin saturation.
Area of Science:
- Condensed Matter Physics
- Spintronics
- Materials Science
Background:
- Magnetic impurities are crucial in spintronics materials.
- The anomalous Hall effect (AHE) is a key phenomenon in spintronics.
- Understanding AHE in systems with spin-orbit coupling is vital.
Purpose of the Study:
- To investigate the anomalous Hall effect in two-dimensional electron systems.
- To explore the influence of magnetic impurities and Rashba spin-orbit coupling on AHE.
- To understand the dependence of AHE on impurity polarization and magnetization.
Main Methods:
- Theoretical study of the anomalous Hall effect.
- Focus on two-dimensional electron systems with Rashba spin-orbit coupling.
- Analysis of the impact of magnetic impurities with varying polarization.
Main Results:
- A highly nonlinear dependence of AHE on impurity polarization was found.
- The linear term of AHE was observed to be independent of spin-orbit coupling strength at low magnetization.
- Resonant enhancement of anomalous Hall conductivity near impurity spin saturation was predicted.
- Sign changes in the Hall effect were identified as possible outcomes.
Conclusions:
- The interplay between magnetic impurities and spin-orbit coupling significantly modifies the anomalous Hall effect.
- Nonlinearities and sign changes in AHE are prominent features in these systems.
- Resonant enhancement offers potential for novel spintronic device applications.
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