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Switching of Perpendicular Magnetization by Spin-Orbit Torque
Lijun Zhu1,2
1State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing, 100083, China.
Advanced Materials (Deerfield Beach, Fla.)
|April 2, 2023
Summary
Researchers are exploring energy-efficient ways to electrically switch perpendicular magnetization for advanced memory and computing. This review covers spin currents, switching mechanisms, and materials for spin-orbit torque (SOT) devices.
Area of Science:
- Spintronics
- Materials Science
- Nanoscience
Background:
- Perpendicular magnetic anisotropy materials are crucial for high-stability nanoscale magnetic memory and computing.
- Efficient, deterministic, and scalable electrical switching of perpendicular magnetization remains a significant challenge.
- The field of spintronics is actively addressing these challenges.
Purpose of the Study:
- To review recent advances in the electrical switching of perpendicular magnetization.
- To summarize challenges and progress in developing energy-efficient perpendicular spin-orbit torque (SOT) memory and logic devices.
Main Methods:
- Review of current research on electrical generation of spin currents.
- Analysis of switching mechanisms and strategies for perpendicular magnetization.
- Examination of switching current density via spin-orbit torque and material selection.
Main Results:
- Progress has been made in understanding spin-orbit torque (SOT) switching mechanisms.
- Various perpendicular magnetic materials are being investigated for SOT applications.
- Prototype SOT memory and logic devices show promise for energy-efficient applications.
Conclusions:
- Significant challenges persist in achieving energy-efficient, deterministic, and scalable electrical switching of perpendicular magnetization.
- Continued research in spintronics is vital for advancing perpendicular SOT applications.
- The development of novel materials and device architectures is key to future nonvolatile magnetic technologies.
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