Noise and discontinuities in GMR transfer curves

High-frequency switching between discrete resistance states has been observed in giant magnetoresistive (GMR) read elements when they are exposed to specific magnetic fields. These high-frequency switching events appear as popcorn like noise spikes when sampled though a high-frequency channel, or as a discontinuity in a resistance versus field, R(H), curve sampled through a low-frequency channel on a quasi-static tester (QST). Both instantaneous and smooth R(H) discontinuities have been found to be caused by high-frequency field dependent GMR switching, and appear different due to filtering effects.