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Updated: Oct 26, 2025
15:58
Measurement of Coherence Decay in GaMnAs Using Femtosecond Four-wave Mixing
Published on: December 3, 2013
5.9K
Spin relaxation in diluted magnetic semiconductors: GaMnAs as example
I V Krainov1, V F Sapega1, G S Dimitriev1
1Ioffe Institute, 194021 St. Petersburg, Russia.
Summary
This study investigates magnetic impurity spin relaxation in diluted magnetic semiconductors above the Curie temperature. Results show spin relaxation rates increase with temperature, supporting mobile carriers as the primary relaxation channel.
Area of Science:
- Condensed Matter Physics
- Materials Science
Background:
- Diluted magnetic semiconductors (DMS) exhibit unique magnetic properties.
- Understanding spin relaxation mechanisms is crucial for DMS applications.
- High concentrations of magnetic impurities can lead to magnetic correlations.
Purpose of the Study:
- To investigate magnetic impurity spin relaxation in DMS above the Curie temperature.
- To explore the role of mobile carriers in mediating impurity interactions.
- To validate a theoretical model with experimental data.
Main Methods:
- Theoretical modeling of spin relaxation.
- Experimental measurement of manganese spin relaxation time in GaMnAs.
- Utilizing spin-flip Raman scattering for measurements.
Main Results:
- The primary spin relaxation channel is identified as mobile carriers.
- Experimental data supports the theoretical model.
- Spin relaxation rate increases with temperature in ferromagnetic samples.
Conclusions:
- Mobile carriers play a significant role in magnetic impurity spin relaxation.
- The findings are consistent with theoretical predictions.
- Temperature dependence of spin relaxation is observed in DMS.
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