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Visualizing Uniaxial-strain Manipulation of Antiferromagnetic Domains in Fe1+YTe Using a Spin-polarized Scanning Tunneling Microscope
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Unconventional Charge-Spin Conversion in Weyl-Semimetal WTe2.
Bing Zhao1,2, Bogdan Karpiak2, Dmitrii Khokhriakov2
1Beijing Advanced Innovation Center for Materials Genome Engineering, School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing, 100083, China.
Advanced Materials (Deerfield Beach, Fla.)
|August 11, 2020
Summary
Topological quantum materials like WTe2 exhibit efficient charge-to-spin conversion, enabling practical spintronic devices. This study demonstrates unconventional spin polarization in WTe2 for room-temperature spintronics.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Mechanics
Background:
- Topological quantum materials possess unique electronic band structures with novel spin topology.
- High charge-to-spin conversion efficiency is expected in these materials.
- Conventional effects like spin Hall and Rashba-Edelstein have limitations.
Purpose of the Study:
- To investigate charge-current-induced spin polarization in the type-II Weyl semimetal WTe2.
- To demonstrate efficient spin injection and detection in graphene using WTe2 up to room temperature.
- To explore unconventional charge-to-spin conversion mechanisms in WTe2.
Main Methods:
- Experimental measurement of spin polarization in WTe2.
- Utilizing charge-to-spin conversion and its inverse phenomenon.
- Electrical creation and detection of spin polarization.
Main Results:
- Observed unconventional charge-to-spin conversion in WTe2, defying crystal symmetry constraints.
- Achieved efficient spin injection and detection in graphene at room temperature.
- Attributed large spin polarization to reduced crystal symmetry, large spin Berry curvature, and novel spin-texture.
Conclusions:
- WTe2 acts as an efficient nonmagnetic spin source for spintronic circuits.
- Findings pave the way for low-power, high-performance nonvolatile spintronic technologies.
- Demonstrated a practical method for electrical spin manipulation in van der Waals heterostructures.
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