Current Control of Magnetism in Two-Dimensional Fe_{3}GeTe_{2}.
Øyvind Johansen1, Vetle Risinggård1, Asle Sudbø1
1Center for Quantum Spintronics, Department of Physics, Norwegian University of Science and Technology, NO-7491 Trondheim, Norway.
Physical Review Letters
|July 9, 2019
Summary
Currents can control magnetism in 2D van der Waals materials like Fe3GeTe2. This spin-orbit torque tuning enables new magnetic anisotropies and the study of 2D phase transitions.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Spintronics
Background:
- Two-dimensional van der Waals systems exhibit emergent magnetic properties.
- Controlling magnetism with electrical currents is a key goal in spintronics.
Purpose of the Study:
- Investigate current-induced control of ferromagnetic properties in 2D van der Waals materials.
- Identify a specific material system where current-induced spin torque is highly effective.
- Explore the impact of spin-orbit torque on magnetic anisotropy.
Main Methods:
- Symmetry arguments to identify suitable material systems.
- Theoretical investigation of current-induced spin torque in Fe3GeTe2.
- Analysis of spin-orbit torque effects on magnetic free energy and anisotropy.
Main Results:
- Fe3GeTe2 exhibits a simple and powerful current-induced spin torque.
- Spin-orbit torque introduces tunable in-plane magnetic anisotropies.
- The system's magnetic state can be tuned from easy-axis to easy-plane and back with increasing current density.
Conclusions:
- Electrical current offers precise control over ferromagnetic properties in Fe3GeTe2.
- This control enables the study of Berezinskii-Kosterlitz-Thouless phase transitions in 2D systems.
- The findings pave the way for novel spintronic devices and fundamental physics exploration.
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