Fig. 1

Vector behavior and influence of particle concentration. (a) The first plot shows the resonance behavior with 70 wt% iron particles. The relative orientation to the applied magnetic field has a strong influence on the absolute signal amplitude. The sensor is only sensitive in the z-direction. (b) Compares sensor elements with different magnetic particle concentrations. The signal increases up to 50 wt% and finally decreases at a concentration of 70 wt%.