Specific features of the magnetoreflection of co-based amorphous ribbons in the IR region

Abstract

The light reflection spectra and the magnetorefractive effect in the cobalt-based amorphous ribbons in the IR spectral region (λ = 2.5–25 μm) are studied. These amorphous alloys are characterized by the magnetoimpedance effect, which is enhanced after thermal and laser annealing. It is found that the magnetoimpedance and magnetorefractive effects correlate with each other. The magnetorefractive effect reveals a feature at λ = 15–20 μm and the change of sign in the wavelength region 20–25 μm. It is shown that, in the first approximation, the optical properties of the amorphous alloys in the IR spectral region can be explained on the basis of a modified Hagen-Rubens relation. It is found that the change in the reflection coefficient of amorphous metal films in the IR spectral region under action of a magnetic field is caused by the change in both their magnetic permeability and conductivity, which is caused by the degree of polarization of localized electronic states at the Fermi level.