3-D Magnetic Angular Sensor Enabled by Spin-Orbit Torque

The application scenarios of magnetic angular position sensors are extensive, spanning diverse fields, such as navigation, medical devices, robotics, automotive industries, and aerospace. However, the fabrication of 3-D angular sensors presents significant challenges, as it necessitates the integration of sensors with varying orientations and precise orientation correction. In this work, we propose a novel 3-D angular position sensor based on the current-induced spin-orbit torque (SOT) effect, which features a simple and compact heavy metal (HM)/ferromagnetic (FM) heterostructure configuration. Spatial angular detection is accomplished by determining two projection angles, which represent the projection of a magnetic field onto three orthogonal planes within a spatial coordinate system. Compared to both commercially available and recently proposed angular position sensors, our design distinguishes itself by enabling 3-D magnetic field sensing with a single device, while maintaining a straightforward and scalable manufacturing process. Experimental results demonstrate that the angular error of the proposed sensor remains below 1° under magnetic fields of less than 15 Oe.