High-Performance Magnetoresistance-Superconducting-Soft-Magnetic Composited Magnetic Sensor

The magnetoresistance-superconducting composited magnetic sensor is a novel high-sensitivity weak magnetic sensor with significant application potential in fields such as biomedical science and geological exploration. However, the current superconducting flux concentrators face the issue of saturation in magnetic field amplification, which limits further improvement in the magnetic field resolution of the composited sensors. This article proposes a new type of magnetoresistance-superconducting-soft-magnetic composited sensor, which utilizes a superconducting planar gradient coil combined with soft magnetic plates to form a composite flux concentration structure. This design not only enhances the magnetic field amplification but also suppresses the interference of magnetic fields in nondetection directions. Theoretical simulations and experimental results indicate that the magnetic field sensitivity of this novel composited sensor is 3.2 times higher than that of magnetoresistance-superconducting composited sensors. This work is of great significance for the research on magnetoresistance sensors.