Effect of doping of molybdenum on the optical properties of glasses of the As—S system
Keywords:arsenic sulfide, molybdenum, spin-coating, optical band gap, Urbach energy
This article discusses the spectral dependences of the absorption coefficient of thin arsenic sulphide films obtained by spin-coating, identified using a single-beam spectrophotometer in the wavelength range of 400–1000 nm. The effect of doping of molybdenum on the optical band gap is studied. While for a pure glass the band gap decreases with higher sulphur concentration, the opposite trend is observed in glass doped with molybdenum. Molybdenum doping also leads to an increase in Urbach energy. The obtained experimental curves are compared with theoretical ab-initio calculations.
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