Influence of DC bias field, excitation and detection frequencies on magnetic Barkhausen noise analysis

Abstract

The micromagnetic Barkhausen emissions, widely known as Barkhausen noise, are quite dependent on excitation and detection frequencies. The input variables to generate these emissions are amplitude, wave form and frequency of magnetic excitation field. When DC bias field is coupled with an AC magnetic field, this complex excitation give rises to distortion of the magnetic hysteresis loop. Recent work showed the frequency dependence of hysteresis curves in ferromagnetic materials. Since there is strong correlation between the location on the B/spl Pi/ loop and Barkhausen noise, comprehending the magnetization mechanisms at each location is essential. The current investigation indicated significant changes in voltage waveforms, pulse height spectra, frequency spectra and RMS voltages of magnetic Barkhausen noise in magnetic materials with different DC bias fields, detection and excitation frequencies. >