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Magnetic Tweezers for the Measurement of Twist and Torque
Published on: May 19, 2014
Spin-transfer-torque-assisted domain-wall creep in a Co/Pt multilayer wire
L San Emeterio Alvarez1, K-Y Wang, S Lepadatu
1School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, United Kingdom.
Physical Review Letters
|May 21, 2010
Summary
We observed domain-wall creep motion in Co/Pt wires using spin-transfer torque. A DC current assisted domain-wall motion, confirming non-adiabatic spin torque effects and quantifying spin-transfer efficiency.
Area of Science:
- Condensed Matter Physics
- Spintronics
- Materials Science
Background:
- Domain-wall (DW) motion is crucial for spintronic devices.
- Understanding creep motion under external stimuli is essential for device optimization.
- Spin-transfer torque (STT) effects are key to manipulating magnetic domains.
Purpose of the Study:
- To investigate field- and current-driven domain-wall creep motion in Co/Pt multilayer wires.
- To analyze the influence of spin-transfer torque on DW creep.
- To quantify the spin-transfer efficiency and understand non-adiabatic contributions.
Main Methods:
- Real-time Kerr microscopy was employed to observe DW motion.
- DC current was applied to study current-driven creep.
- A theoretical model incorporating bidirectional spin-transfer effects and Joule heating was developed.
Main Results:
- DC current assisted DW creep in the direction of electron flow, indicating STT effects.
- Both field- and current-driven creep exhibited the same dynamical exponent (μ=1/4).
- Spin-transfer efficiency was quantified as 3.6±0.6 Oe cm²/MA, highlighting non-adiabatic STT contributions.
Conclusions:
- Spin-transfer torque significantly influences domain-wall creep motion.
- Non-adiabatic effects play a substantial role in spin torque.
- The study provides quantitative insights into STT efficiency in Co/Pt multilayer wires.
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