Spin-Orbit Torque Sensors with Offset Cancellation for 3D field measurements
Spin-Orbit Torque ( SOT) sensors have garnered significant attention in recent years due to their potential for high sensitivity and low zero field offset [1,2,3] . This work provides a comprehensive overview of recent advancements in SOT sensors, focusing on key aspects including operational principles and active offset (zero field error) compensation.
This work delves into the latest developments in SOT sensor applications, encompassing magnetic field detection with active offset compensation and high sensitivity readout. In this study, we present a device designed for measuring magnetic fields below 1 mT with high sensitive readout in all 3 directions, while also compensating for offset in all three dimensions by spinning current techniques [4] and SOT modulations of the magnetization [3]. Furthermore the concept of a combined TMR Hall effect sensor, utilizing SOT, will be introduced. This combines the high sensitive TMR readout of Hall based devices, which allows for the cancellation of the zero field error .
Spin-Orbit Torque, Sensors, Operational Principles, Offset Compensation, High Sensitivity
[1] Luo, Ziyan & Xu, Yanjun & Yang, Yumeng & Wu, Yihong. (2018). Magnetic angular position sensor enabled by spin-orbit torque.
[2] Li, R., Zhang, S., Luo, S. et al. A spin-orbit torque device for sens- ing three-dimensional magnetic fields. Nat Electron 4, 179-184 (2021). https://doi.org/10.1038/s41928-021-00542-8
[3] Koraltan, S, et al. "Single-device offset-free magnetic field sensing with tunable sensitivity and linear range based on spin-orbit torques." Physical Review Applied 20.4, 044079 (2023).
[4] Munter, P.J.A. (1990) A Low-Offset Spinning Current Hall Plate. Sensors and Ac- tuators A: Physical, 21-23, 743-746. https://doi.org/10.1016/0924-4247(89)80069- X