Premium
Optical Band Gap, Infrared Absorption and Thermal Diffusivity of Ge–Ga–Se Glasses
Author(s) -
Thomas Sh.,
Philip J.
Publication year - 1997
Publication title -
physica status solidi (b)
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.51
H-Index - 109
eISSN - 1521-3951
pISSN - 0370-1972
DOI - 10.1002/1521-3951(199704)200:2<359::aid-pssb359>3.0.co;2-e
Subject(s) - thermal diffusivity , materials science , coordination number , percolation threshold , band gap , maxima , infrared , percolation (cognitive psychology) , thermal , absorption (acoustics) , quenching (fluorescence) , rigidity (electromagnetism) , analytical chemistry (journal) , thermodynamics , optics , chemistry , fluorescence , electrical resistivity and conductivity , physics , composite material , optoelectronics , art , organic chemistry , chromatography , quantum mechanics , neuroscience , performance art , biology , art history , ion
The results of our measurements on the variation of optical band gap E g and thermal diffusivity α, with average coordination number Z are reported and discussed for Ge x Ga 5 Se 95— x semiconducting glass samples. The samples are prepared by the melt quenching technique at a cooling rate of approximately 10 2 K/s. In the variation of E g with Z of these glasses, a maximum in E g is observed at Z = 2.73 corresponding to the chemical threshold of the system. Threshold maxima are seen at Z values of 2.42 and 2.67 in the α versus Z curves of these glasses. These features are explained in terms of mechanical stiffening of the glass network due to threshold percolation of rigidity and a two‐ to three‐dimensional structural transition, both driven by the average coordination of the atoms in the network. The results confirm the existence of effects due to topology and local chemical ordering in these glasses.