Effects of transverse fields on spin-valve sensor magnetic field measurements

Spin-valve sensors have become a popular magnetic sensor, used in many applications such as magnetic imaging or hard drive heads. Spin-valves are designed to measure only one component of the magnetic field. This component is determined by the composition of the spin-valve layers, the manufacturing conditions, shape anisotropy, and other design decisions. We took magnetic images of L-shaped samples in order to determine if magnetic fields transverse to the direction of measurement affect spin-valve sensors. Specifically, we used a 2 \textmu m by 4 \textmu m Cu-Mn-Ir spin-valve sensor to take image of chips with ``L-shaped'' currents. We find that transverse fields can significantly affect the measurement direction of spin-valve sensors.