Optical properties and electronic structure of alloys Co$_{2}$Cr$_{1-x}$Fe$_{x}$ Al ($x$ = 0, 0.4, 0.6, 1.0)

The results of the investigation of the optical properties and calculations of the density of states $N(E)$ of the Heusler alloys Co$_{2}$Cr$_{1-x}$Fe$_{x}$ Al ($x$ = 0, 0.4, 0.6, 1.0) have been presented. It has been found that the band spectrum substantially changes, especially in the vicinity of the Fermi level, due to the concentration transition from Co$_{2}$FeAl to Co$_{2}$CrAl. These changes are accompanied by significant changes in the optical properties. The optical properties of the Co$_{2}$FeAl alloy are typical of metals. The anomalous behavior of the optical properties of the alloys with $x$ = 0, 0.4, and 0.6 is determined by the electronic states at the Fermi level.