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Updated: Jun 5, 2026
06:49
Radio Frequency Magnetron Sputtering of GdBa2Cu3O7−δ/ La0.67Sr0.33MnO3 Quasi-bilayer Films on SrTiO3 (STO) Single-crystal Substrates
Published on: April 12, 2019
Designing Magnetic Topological Insulator Trilayers for Highly Efficient Spin-Orbit Torque Switching
Ling-Jie Zhou1, Deyi Zhuo1, Han Tay1
1Department of Physics, The Pennsylvania State University, University Park, Pennsylvania 16802, United States.
Nano Letters
|June 4, 2026
Summary
Spin-orbit torque (SOT) efficiently controls magnetization in magnetic topological insulators. A substrate-induced charging effect governs SOT switching of quantum anomalous Hall edge currents, enabling spintronic devices.
Area of Science:
- Spintronics
- Condensed Matter Physics
- Materials Science
Background:
- Spin-orbit torque (SOT) offers low-power electrical control of magnetization.
- Magnetic topological insulators (TIs) are promising for spintronic applications due to their unique electronic properties.
Purpose of the Study:
- To investigate SOT-driven magnetization reversal and edge-current chirality switching in magnetic TI heterostructures.
- To understand the role of substrate effects and heterostructure design in controlling SOT switching.
Main Methods:
- Molecular beam epitaxy (MBE) for synthesizing magnetic TI trilayers.
- Electrical transport measurements to analyze SOT switching and QAH edge currents.
- Utilizing SrTiO3(111) substrates with controlled layer thicknesses.
Main Results:
- SOT-driven switching is governed by a substrate-induced chemical potential asymmetry between TI layers.
- Switching polarity and efficiency are tunable via heterostructure design, gate voltage, and magnetic fields.
- Demonstrated large SOT switching ratio attributed to chemical potential asymmetry.
Conclusions:
- Chemical-potential asymmetry is identified as the key mechanism for efficient SOT switching.
- Establishes a pathway for electrical control of edge currents in quantum anomalous Hall insulators.
- Paves the way for developing QAH-based logic and memory devices.
Keywords:
Magnetic topological insulatorchemical potential asymmetryedge-current chiralityheterostructure designspin−orbit torque switchingMore Related Videos
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