L.V.Poperenko, A. Roeseler*
Optical measurements according to scheme of Beattie-Conn polarimetric
method using Fourie spectrometer IFS-55 were carried out within spectral
range 2-25 mm for samples of Fe- or Ni-based amorphous alloys at 4 orientations
of the ribbon longitudinal axis relatively to the plane of light incidence.
Having determined the deviations of ellipsometrical parameters for light
reflected from the ribbon surface in dependence on its orientation in the
own plane, the level of deformational strains changes in the subsurface
layer of amorphous ribbons fabricated by rapid melt quenching method was
estimated. The existence of elastic-stressed state within subsurface
layer for each ribbon side and the difference of characteristics
for such state in as-cast ribbons of amorphous alloys not only on both
sides but also in dependence on the depth from each of these two surfaces
was revealed. To find the structural modification in disordered material,
the Raman light scattering spectroscopic experiment was carried out, too.
The observed two maxima in Raman light scattering spectra of these alloys
provide the evidence for mere change in the photon density of states just
below 200 cm-1. The deviation of the dielectric function
of such structures from the well-known Drude-like dependence
may be explained as a result of the appearance of weak electron localisation
in the vicinity of the Fermi level.