| Chalcogenide glasses have high transmittance in infrared region, which are important optical materials and optoelectronic materials. Amorphous chalcogenide films have attractive prospects in the area of modern integrated optical devices. Amorphous GeSx(x=2,4,6), GeSex(x=2,4,6),90GeS2-5Ga2S3-5CdS,80GeS2-10Ga2S3-10KBr and (1-x)(4GeSe2-Ga2Se3)-xKBr (x=0,0.1,0.2,0.3) films have been prepared by the pulsed laser deposition method in this paper. By using a variety of modern analytical tools and methods, the films' compositions, structures and optical properties of the glass networks were determined. The main results and conclusions are as follows,(1) Components of the films prepared by the pulsed laser deposition method are small deviation from the targets. The films are smooth, amorphous and their surface roughness is small before and after annealing, except that the film with the component of 0.7(4GeSe2-Ga2Se3)-0.3KBr has microcrystalline after annealing.(2) Optical transmission spectra and absorption spectra show that the short wave-length absorption edges and optical bands of GeSx (x=2,4,6) films are blue-shifting with the increase of S content (from 2.59 to 2.86eV), while the refractive indices decrease with S content. The amount of Ge-Ge decreases with the increase of S content, which caused the average bond energy became larger and increased the optical band gaps of GeSx films. The increase of S content of glass films leads to the decrease of refractive index because of the higher polarization and the larger radius of Ge4+cation. The optical band gaps increased after annealing correspondingly. Raman spectra show that [GeS4/2] tetrahedrons are the main units in GeSx films, which are edge-or vertex-sharing connecting. [GeS4/2] and [GaS4/2] tetrahedrons are the main units in 80GeS2-10Ga2S3-10KBr and 90GeS2-5Ga2S3-5CdS films.(3) The optical band gaps of GeSex(x=2,4,6) films decrease with the increase of Se content (from 1.95 to1.90eV), while the refractive indices increase with S content. The optical band gaps correspondingly increased after annealing, too. For (1-x) (4GeSe2-Ga2Se3)-xKBr (x=0,0.1,0.2) films, the optical bands increase with the increase of KBr content (from 1.98 to 2.24eV), while the refractive indices decrease.(4) The films with the components 0.8GeSe2-0.2Ga2Se3 and GeSe4 show significant photo-induced volume expansion, photo-darkening and photo-induced anisotropy. The relative volume expansions are 3.3% and 9.3%, respectively. And photo-induced anisotropy is 5.8% and 7.1%, respectively. The mechanism of photo-darkening is that photo-induced light irradiation caused more defects in these glass films, which strengthened the disorder of the glass films and increased the density of local states above the valence band. The mechanism of photo-induced volume is that light made the layer structures with the charge effect in the chalcogenide glass films, which have charge repulsion between the layer structures. For the photo-induced anisotropy, the effect of electric field of the polarized light caused the connecting between the IVAP and the neighboring atoms changed in spatial arrangement.(5) 90GeS2-5Ga2S3-5CdS films were polarized under electric field/temperature field and the second harmonic signal generation (SHG) was detected. The largest second-order nonlinear coefficient reachesχ(2)=3.83pm/V. Analysis of the electric field poling conditions on second-order nonlinear coefficient shows that polarized electric field plays the role of driving force upon the dipoles'orientation. Temperature polarization conditions have a dual role in the polarization process for the glass films. One is that temperature polarization made the dipoles out of the glass network constraints, which is conducive to the arrangement of dipoles. Secondly, the high temperature made the thermal motion of dipoles too violent, which in turn weakened the orientation of the dipoles.
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