Spontaneous Hall effect and resistivity of Fe-Co-Ni-base glasses

Abstract

The spontaneous Hall effect and dc resistivity have been measured at room temperature in the glassy alloy series Fe80-xCoxB20 (0≤x≤80 at.%) and Fe80-xNixB20 (0≤x≤60 at.%) and in Co40Ni40B20 glass. The density-derived thicknesses used herein give smaller values of Rs and ρ than generally reported for metallic glasses. Because of the relatively large resistivities of metallic glasses, ρ10-4 cm, the nonclassical side-jump mechanism is expected to dominate the spontaneous Hall effect. The magnitude of the side jump in Fe80B20 glass is comparable to that in crystalline Fe and Fe-base dilute alloys, viz. 10-8 cm. The spontaneous Hall conductivity γHs shows a proportionality to the magnetostriction λs as predicted theoretically with a slope that is close to that observed in crystalline Fe-Ni alloys. The compositional dependence of γHs is interpreted in terms of a split-band model in which charge is transferred from boron to the transition-metal d states in the glassy alloys. The applicability of the split-band model to these data implies that an intrinsic spin-orbit interaction involving the itinerant d electrons is effective here and not a spin-other-orbit interaction. © 1978 The American Physical Society.