The impact of proton ion irradiation on Se70Te20In10 thin films: Linear and non-linear optical properties for photonic applications

The examination of the linear and non-linear optical features was conducted on amorphous ternary Se₇₀Te₂₀ In₁₀ thin films, which were exposed to proton irradiation energy of 3 MeV at varying fluences of $5\times {10}^{13}$, $5\times {10}^{14}$, $5\times {10}^{15}$ and $5\times {10}^{16}$ ions/cm². The bulk sample was produced using the melt quenching method, and subsequently, thin films were obtained through electron beam evaporation. Calculations of linear and non-linear optical parameters were carried out based on transmittance and reflectance data acquired from UV–Vis–NIR spectroscopy spanning 300–2500 nm. Field emission scanning electron microscopy (FESEM) and X-ray diffraction (XRD) confirmed an amorphous phase in the films. The optical parameters showed strong dependency on the proton radiation fluence. In addition, the existence of minima or maxima for a number of parameters at a fluence of $5\times {10}^{14}$ ions/cm² showed that this was the optimum fluence. The linear and non-linear properties showed that the sample have potential applications in photonic devices.