Accurate Determination of Optical Functions of Ge-As-Te Glasses via Spectroscopic Ellipsometry

Variable angle spectroscopic ellipsometry technique was used to characterize optical functions of chalcogenide glasses from Ge–As–Te system in broad spectral range (300 nm–20 μm). Measured real and imaginary parts of pseudodielectric function were modeled with Cody–Lorentz approach and Sellmeier equation. Very good agreement between experimentally measured and modeled imaginary and real parts of pseudodielectric functions leads to precise determination of optical functions (refractive index, extinction coefficient) of studied Ge–As–Te glasses in extremely broad spectral range covering UV–Vis‐NIR‐MIR. The method is generally applicable for other glasses and amorphous materials.