Comparative analysis of some 2-nd International Conference on Oxide and Non-Oxide Materials for Optoelectronics 19-22 December 2013, Borovetz Bulgaria Radina’s way Hotel Comparative analysis of some physico-chemical properties of the glassy systems (GeTe5)100-xInx and (GeSe5)100-xInx Vl. Ivanova Stoilova, Y. Trifonova, P. Petkov Laboratory of Thin Film Technology, Department of Physics, University of Chemical Technology & Metallurgy

University of chemical technology and metallurgy

Abstract Our study concerns about these two glassy systems, (GeTe5)100-xInx and (GeSe5)100-xInx, which contain different chalcogen elements. Se and Te-rich chalcogenide glasses are interesting because of their use in switching and memory devices. As a result of the addition of In new properties are expected, which can be related with structure transitions. The investigation of the physico-chemical properties gives more information about the real structure of the glasses. Some physico-chemical characteristics have been obtained as density (), compactness (), molar volume (Vm), Nco, E and they are correlated with the mean coordination number (Z). Keywords: Chalcogenide glasses, physico-chemical properties, structure. 2-nd International Conference on Oxide and Non-Oxide Materials for Optoelectronics

Experimental Bulk samples (GeCh5)1-xInx, were Ch=Se or Te and x=5, 10, 15, 20 mol % In were prepared in the conventional way by melting a mixture of high purity elemental Ge, Se/Te and In in an evacuated quartz ampoules at 1000◦C for 4h. Rapid quenching in ice-water bath was used to obtain the bulk amorphous material.

In the GeSeIn system the Se atoms are replaced by In atoms and the density increases because the masse of Se is smaller then this one of the In. For the other system the replacement of Te atoms with In leads to the decrease of density because the masse of In is smaller than this one of Te. Fig. 1 Graphical relation between the density and the coordination number of the glasses. Fig. 2 Graphical relation between the molar volume and the coordination number of the glasses. 2-nd International Conference on Oxide and Non-Oxide Materials for Optoelectronics

Results Fig. 3 Graphical relation between the compactness and the coordination number of the glasses. 2-nd International Conference on Oxide and Non-Oxide Materials for Optoelectronics

Results Composition E, 10-19 J ZGlass Na Nb Nco Ge16Te79In5 3.74 2.37 1.18 1.73 2.92 Ge15Te75In10 3.88 2.40 1.20 1.80 3.00 Ge14Te71In15 4.04 2.43 1.22 1.87 3.08 Ge13Te67In20 4.20 2.47 1.23 1.93 3.17 Ge16Se79In5 3.53 1,18 1,72 2,9 Ge15Se75In10 3.61 1,2 1,8 3 Ge14Se71In15 3.7 1,215 1,86 3,075 Ge13Se67In20 3.79 1,23 1,92 3,15 Nco number of constraints per atom, Na and Nb – radial and axial bond strengths. 2-nd International Conference on Oxide and Non-Oxide Materials for Optoelectronics

Conclusion From the analysis of the experimental data we can conclude that the system GeTeIn is more suitable for photo and thermoinduced changes.

Thank you for your attention! “This presentation has been produced with the financial assistance of the European Social Fund, project number BG051PO001-3.3.06-0014. The author is responsible for the content of this material, and under no circumstances can be considered as an official position of the European Union and the Ministry of Education and Science of Bulgaria”.