Magnetic hysteresis calculation of sensors based on orthoferrites

Passive and wireless magneto-optical sensors based on orthoferrite crystals are developed. The sensor's response on an oscillating magnetic field show irregularities in the output signal if no stabilizing gradient field is provided. This behavior is caused by the large domain size and the domain wall motion in the orthoferrite crystal. The simulation of the hysteresis and the calculation of the magnetization curves of the crystal plate were done in order to predict the behavior of the material at different field excitations. Using the so-called energetic model yielded an acceptable correlation between the measurement hysteresis and calculation.