The homogeneous GeS2-In2S3-CsI glassy samples were prepared by conventional melt-quenching method. When the molar ratio of In2S3 to CsI remains 1, the non-crystalline region can extend to the composition 0.4GeS2-0.3In2S3-0.3CsI. And with the addition of CsI, the glass-forming ability of this serial glass reaches its maximum at the composition 0.8GeS2-0.1In2S3-0.1CsI. According to the Raman spectra, the microstructure of these glasses is mainly constituted by GeS4 and InS 4-x Ix tetrahedra, which are interconnected by the bridging sulfur atoms; meanwhile, the ethane-liked structural units S3Ge-GeS3 can be formed because of the lacking of sulfur; Cs+ ion, which is added from CsI, exists as the nearest neighbor of I-ion in the glassy network.
Ge-Ga-Ag-S chalcogenide glasses with the composition Ge30Ga3Ag4S63 were obtained by the conventional melt-quenching method. According to the visible-infrared and infrared spectra, Ge30Ga3Ag4S63 chalcogenide glass possesses wide transmittance window from 510 nm in the visible region up to 11.5 μm in the infrared region. And the present glass has better glass-forming ability (the difference between glass transition temperature and the peak temperature of crystallization is larger than 100 ℃). Utilizing maker-fringe technique, a prominent second-harmonic generation was observed in Ge30Ga3Ag4S63 chalcogenide glass after irradiated by an electron beam (Accelerating voltage: 25 kV; Irradiating current: 15 nA; Irradiating time: 10 min). And the mechanism of second-harmonic generation in the Ge-Ga-Ag-S system glasses was discussed.
To find new chalcogenide glass possessing larger second-order non-linearity, glasses with compositions Ge-Ga-X-S (X=P, As, Sb) were prepared via melt quenching technique. The amorphous nature of all the compositions of the as-quenched glasses was confirmed by X-ray diffraction(XRD). The glassy thermal properties of the as-quenched glasses were established by differential thermal analyses(DTA). The glass structure was studied by RAMAN spectra and the second order nonlinearity was studied by the Maker Fringe method after the electron beam poling(EBP) and electric/temperature field poling(ETFP) respectively. Additions of various pnicogen atoms into the Ge-Ga-S glasses lead to the difference in the second order nonlinearity of the glass. It's found that glasses with different structures result in different SHG intensities, and even more, a large second order nonlinear susceptibility X(2) of about 9 pm/V was obtained for all the glasses and the reasons for such a large susceptibility were analyzed.
