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Published on: December 3, 2013
Domain-wall resistance in ferromagnetic (Ga,Mn)As
D Chiba1, M Yamanouchi, F Matsukura
1ERATO Semiconductor Spintronics Project, Japan Science and Technology Agency, 1-18 Kitamemachi, Aoba-ku Sendai, 980-0023, Japan.
Physical Review Letters
|April 12, 2006
Summary
Researchers investigated domain wall resistance in (Ga,Mn)As, identifying extrinsic contributions from Hall field polarity changes and intrinsic contributions from spin mistracking, which significantly exceeds anisotropic magnetoresistance.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Spintronics
Background:
- Domain walls (DWs) in magnetic materials are crucial for spintronic devices.
- Understanding resistance contributions at DWs is essential for device performance.
- Perpendicular magnetic anisotropy in (Ga,Mn)As presents unique domain wall behavior.
Purpose of the Study:
- To quantitatively determine extrinsic and intrinsic contributions to domain wall resistance.
- To elucidate the physical mechanisms underlying domain wall resistance in (Ga,Mn)As.
- To correlate resistance with microstructural features designed to pin domain walls.
Main Methods:
- Fabrication of microstructures to pin domain walls in (Ga,Mn)As.
- Electrical transport measurements to probe domain wall resistance.
- Analysis of Hall effect and magnetoresistance to separate resistance contributions.
Main Results:
- Extrinsic resistance is quantitatively explained by polarity changes in the Hall electric field at domain walls.
- Intrinsic resistance is found to be an order of magnitude greater than anisotropic magnetoresistance.
- Intrinsic resistance is consistent with disorder-induced mistracking of carrier spins in spatially varying magnetization.
Conclusions:
- Domain wall resistance in (Ga,Mn)As has significant extrinsic and intrinsic components.
- Spin mistracking due to disorder is the dominant intrinsic contribution to domain wall resistance.
- Microstructure design effectively probes and separates different resistance mechanisms.
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