Fluence effects on the magnetic properties of Fe81B13.5Si3.5C2 metallic glass produced by pulsed laser deposition

Abstract

A metallic glass target of Fe81B13.5Si3.5C2 ribbon was ablated under pulsed focused laser irradiation at a high fluence, Φ=3, 5, 6, 7.5, and 10 J/cm2. X-ray diffraction was performed on the resulting films, demonstrating the amorphous nature of the samples. Hysteresis loop measurements were recorded at 4.2 K in an applied magnetic field of 1.5 T to show differences in the saturation magnetic moment and coercivity between the as-cast ribbon and laser-ablated films. Conversion electron Mössbauer spectra were used to obtain the fluence dependence of the hyperfine magnetic field and magnetic texture parameter. At low laser fluences, the magnetic moments were predominantly oriented in the plane of the film. For intermediate values of the laser fluence, a random distribution of magnetic-moment directions was achieved. For high laser fluences, however, an out-of-plane orientation of the magnetic moments resulted. The films have prospective applications in magnetic sensors, switches, and concentrators.