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Current-induced switching of perpendicularly magnetized magnetic layers using spin torque from the spin Hall effect
Luqiao Liu1, O J Lee, T J Gudmundsen
1Cornell University, Ithaca, New York 14853, USA.
Physical Review Letters
|September 26, 2012
Summary
The spin-Hall effect in platinum (Pt) generates sufficient spin torque to efficiently switch cobalt (Co) magnetization. This offers a promising pathway for reliable memory and logic devices.
Area of Science:
- Spintronics
- Condensed Matter Physics
- Materials Science
Background:
- Perpendicularly magnetized bilayers are crucial for magnetic storage.
- Spin-torque is a key mechanism for manipulating magnetization.
Purpose of the Study:
- To investigate the spin-Hall effect (SHE) in Pt/Co bilayers.
- To determine the efficiency of SHE-induced spin torque for magnetization switching.
Main Methods:
- Theoretical calculations of the switching phase diagram.
- Comparison of calculated results with experimental data.
Main Results:
- SHE in Pt generates significant spin torque for Co magnetization switching.
- Calculated phase diagrams show quantitative agreement with experiments.
- Optimized SHE torque offers comparable critical currents and improved reliability over conventional methods.
Conclusions:
- SHE torque is a viable mechanism for efficient magnetization switching.
- SHE torque has potential applications in advanced memory and logic devices.
- SHE torque may also influence domain wall motion in Pt/ferromagnet systems.
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