Structural and Optical Properties of Ti-Doped InTe Thin Films

Abstract

Thin films of Ti-doped indium telluride (InTe) chalcogenide were prepared by the magnetron co-sputtering method. The optical and structural properties were investigated by various tools after the thermal treatment. All annealed films were highly polycrystalline with (211) as the preferred orientation. Raman spectra results confirm that the structure of the InTe films can be adjusted by Ti dopants. The transmittance is high in the near-infrared region. The refractive index (n) and extinction coefficient (k) of the films were measured by a Spectroscopic Ellipsometer. The optical band gaps increase from 1.56 to 1.85 eV with the increasing concentration of Ti. The third-order nonlinear optical properties of the thin films were investigated by applying the open-aperture Z-scan method with femtosecond laser excitation at 800 nm wavelength. The results show reverse saturation absorptions which show the potential value of the films in optical limiting applications. The nonlinear absorption coefficient was calcula...