Optical features of zinc selenide, silver iodide and its two-phase composite nanostructures

The goal of this work is the investigation of optical spectra features of zinc selenide (ZnSe), silver iodide (AgI) and its two-phase composite AgI-ZnSe nanostructures produced by laser ablation method, which can be used to design optical sensors and diffractive structures in integrated optics. Shifted to blue wavelengths relatively to the bulk semiconductor material band edge transmission spectra minima have been discovered for the ZnSe and AgI-ZnSe films. The observed minima of the transmission spectra are peculiar to the quantum energy spectra of semiconductor nanostructures. Discovered transmission spectra minima for the ZnSe and AgI-ZnSe films shifted to the short-wavelength region from the energy of the bulk material band gap can be the evidence of nanocrystals formation during the film growth by laser ablation, and which are characterized by the energy spectrum quantization and lower electron and upper hole quantum confinement levels shifts from the bottom of the conduction and the top valence bands, respectively.