Linear and non linear optical properties of Sb<SUB>2</SUB>Se<SUB>3</SUB> thin films elaborated from nano-crystalline mechanically alloyed powder

International audienceSb2Se3 powder is achieved by mechanical milling of Sb and Se elements. X-ray diffraction analysis indicated the formation of Sb2Se3 orthorhombic phase. The latter finding is confirmed by both X-ray photoelectron spectroscopy characterization and Raman spectroscopy. Magnetic measurement revealed the ferromagnetic character of Sb2Se3 powder. Thin films were obtained by thermal deposition using Sb2Se3 powder as a precursor. Optical measurements carried out on thin films showed a high absorption coefficient and a direct band gap of 1.61 eV. The material has then potential application in photovoltaic conversion. Thin film refractive index dispersion ( n) obeys Cauchy dispersion equation. n is investigated and found to comply with Wemple-DiDomenico single oscillator dispersion model. The energy E 0 of the oscillator and E d dispersion energy are derived from the refractive index investigation. Spitzer-Fan model exploitation was allowed to derive the high-frequency dielectric constant ɛ ∞ and the carrier density N/ m* ratio. Additionally, Verdet constant V is determined based on the refractive index dispersion study. Furthermore, the nonlinear susceptibility χ (3) as well as nonlinear refractive index are determined for Sb2Se3 thin films. The nanostructure of the material is likely responsible not only for the high nonlinear characteristics but also for the low magnetic character in Sb2Se3