Анотація:
We investigate the optical properties of Cu-Fe alloys in a wide interval of
concentrations (7.5–30 at. %) and in a wide spectral interval (0.25–7 µm). An additional
absorption associated with interband electron transitions from localized states of
impurities to the Fermi level has been revealed in the 0.98–1.9-eV spectral range. The
energy bands in Cu-Fe alloys are almost undeformed and similar to copper ones, while
the Fe impurity forms localized d-bands at a distance of about 1.0-1.6 eV from the Fermi
level. For high impurity concentrations, the experimental optical conductivity spectra
σ (hν) of the alloys are determined by a superposition of the spectra of Fe and the
appropriate solid solution with the corresponding weight coefficients. The obtained
experimental data allow one to calculate the density of states N (Е) which is related to the
impurity band.