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Current-induced polarization and the spin Hall effect at room temperature
1Center for Spintronics and Quantum Computation, University of California-Santa Barbara, CA 93106, USA.
Physical Review Letters
|October 10, 2006
Summary
This study images electrically induced spin polarization in zinc selenide (ZnSe) using Kerr rotation spectroscopy. Researchers observed current-induced spin polarization and the spin Hall effect across a wide temperature range.
Area of Science:
- Solid State Physics
- Spintronics
- Semiconductor Physics
Background:
- Understanding electrical control of electron spin is crucial for spintronics.
- Zinc Selenide (ZnSe) is a semiconductor with potential applications in spin-based devices.
Purpose of the Study:
- To investigate electrically induced spin polarization in n-type ZnSe epilayers.
- To characterize the spin Hall effect in ZnSe and determine its conductivity.
Main Methods:
- Kerr rotation spectroscopy was employed to image electron spin polarization.
- Electrical transport measurements were performed on n-type ZnSe epilayers.
Main Results:
- Observed current-induced in-plane spin polarization, with spin lifetimes dependent on doping density.
- Detected the spin Hall effect, showing electrically induced out-of-plane spin polarization.
- Estimated spin Hall conductivity at 20 K as 3+/-1.5 Omega(-1) m(-1)/|e|, consistent with extrinsic mechanisms.
- Both phenomena were observed across a broad temperature range (10–295 K).
Conclusions:
- Electrical currents can induce significant spin polarization in n-type ZnSe.
- The observed spin Hall effect in ZnSe is consistent with extrinsic scattering mechanisms.
- ZnSe is a viable material for exploring electrical spin manipulation at various temperatures.
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