Figure 5

Power dependency of the antiparallel exchange biased SAW sensor’s performance. (a) Sensitivity as a function of applied magnetic DC bias field swept from − 10 mT to + 10 mT (full lines) and vice versa (dashed lines) for different excitation powers. Only the region of high sensitivity from − 1.2 mT to + 1.2 mT is shown. (b) Magnetically induced insertion loss as a function of applied DC magnetic field for different excitation powers measured from − 10 mT to + 10 mT. The losses are normalized to 0 dB, where 0 dB then corresponds the insertion loss in magnetic saturation. (c) Phase noise spectra of the same sensor at different excitation powers. For every excitation power a DC bias field was applied which corresponds to the point of highest sensitivity. (d) Phase noise at 10 Hz and 100 Hz and the respective maximum sensitivity as a function of excitation power.