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The heterostructures of $\text{Cr}_{1}\text{Ag}_{45}\text{TiO}_{2}$, $\text{Cr}_{1.2}\text{Cu}_{40}\text{TiO}_{7}$, and $\text{Cr}_{1.2}\text{Cu}_{43}$, prepared by chemical vapour deposition method were investigated using ellipsometric measurement method in order to calculate optical constants by two models namely Tautz-Lorentz and the effective medium model at the vicinity of the principal angle of the light incidence. Each sample contains a buffer layer of chromium that was deposited on quartz glass. Besides thin upper layer of $\text{TiO}_{2}$ was deposited on sample by high-frequency magnetron sputtering.
As a result of optical measurements, within the range from 190$nm$ to 25$\mu m$ and carried out by Semilab SE-2000 device, two ellipsometric parameters $\psi$ (an azimuth of the restored linear polarization) and $\Delta$ (a phase shift between the p- and s-components of the polarization vector) were obtained, then the values were compared for the given heterostructures including a thin layer of copper and silver. Thereby it was found that upper layer of $\text{TiO}_{2}$ deposited on surface does not significantly affect the absorption of these structures in the selected wavelength range. Eventually it was demonstrated 8$\%$ difference between the values of the reflection coefficient for the Tautz-Lorentz model and the values for the effective medium model. In addition it was found that heterostructure which contains only a pure layer of copper without upper layer of $\text{TiO}_{2}$ gives the largest difference for the values of the reflection coefficient when compare these two models (approximately $n$- 10$\%$, $\kappa$-15$\%$, $\sigma$- 4$\%$, $R$-10$\%$ ) and may indicate the formation of such oxide film on sample surface.
| Topics | Session A. Physics of condensed matter and spectroscopy |
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