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Visualizing Uniaxial-strain Manipulation of Antiferromagnetic Domains in Fe1+YTe Using a Spin-polarized Scanning Tunneling Microscope
Published on: March 24, 2019
Chiral spin torque at magnetic domain walls
Kwang-Su Ryu1, Luc Thomas, See-Hun Yang
1IBM Almaden Research Center, 650 Harry Road, San Jose, 95120 California, USA.
Nature Nanotechnology
|June 18, 2013
Summary
Spin-orbit interactions drive domain walls in ultrathin magnetic wires at high speeds. A chiral effective field from Dzyaloshinskii-Moriya interaction and spin Hall currents control this motion, enabling new spintronic devices.
Area of Science:
- Spintronics
- Condensed Matter Physics
- Materials Science
Background:
- Spin-polarized currents manipulate magnetization and drive magnetic domain walls via spin transfer torques.
- Unusual domain wall motion (opposite direction, higher speeds) observed in ultrathin magnetic wires.
Purpose of the Study:
- Investigate the mechanisms behind anomalous domain wall motion in ultrathin magnetic wires.
- Elucidate the role of spin-orbit interactions in current-driven domain wall dynamics.
Main Methods:
- Experimental measurement of current-driven domain wall motion in Co/Ni/Co trilayers.
- Application of magnetic fields to influence domain wall behavior.
- Analysis of domain wall dynamics in response to applied fields and currents.
Main Results:
- Observed an internal effective magnetic field acting on domain walls, alternating in direction.
- Identified Dzyaloshinskii-Moriya interaction at Co/Pt interfaces as the source of this chiral field.
- Demonstrated that this field, coupled with spin Hall currents, drives domain walls in unison.
Conclusions:
- Spin-orbit interactions, specifically Dzyaloshinskii-Moriya interaction and spin Hall effect, govern domain wall motion in ultrathin magnetic films.
- This mechanism explains the high-speed, reversed domain wall motion.
- Findings pave the way for novel spintronic device development.
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