Design of Element Configuration on Magnetic Rotation Angle Sensor with Spin-Valve Film

To reduce the error of a magnetic rotation angle sensor, we investigated the effect of sensor element configuration on the output signal of the sensor by using numerical calculations. The sensor elements were made of spin-valve films with a large shape-induced anisotropy. The magnetization of elements was calculated by minimizing the magnetic energy in a framework of the Stoner-Wohlfarth model. The sensor response was calculated as a function of the relative angle between the spin-valve elements. The error of signals was minimized when the relative angle was 99.5 degrees. It is clear that this configuration is robust against the variation of shape-induced anisotropy. (C) 2010 The Japan Society of Applied Physics