Influence of structurization of amorphous Fe73.5Si13.5B9Nb3Cu1 alloy on its spectral properties

The optical properties of Fe73.5Si13.5B9Nb3Cu1 ferromagnetic alloy in the amorphous, nanocrystalline, and crystalline states have been investigated by optical ellipsometry in the spectral range of 0.22–18 μm. It is established that the crystallization of alloy during heat treatment leads to a significant change in its optical constants, as well as the frequency dependences of dielectric functions calculated based on these constants. The structural ordering is accompanied by a considerable increase in the intensity of the fundamental absorption band and an occurrence of its blue shift. Some characteristics of conduction electrons are determined, the numerical values of which also depend on the degree of atomic order.