Synthesis and properties of GeS2-Ga2S3:NdCl3 and GeS2-Ga2S3:Nd2O3 glasses

High purity (GeS2)(80-x)(Ga2S3)(20). xNdCl(3) (x = 1, 2, 3) and (GeS2)(79)(Ga2S3)(20). Nd2O3 glasses were prepared and their thermal and optical properties measured. The GeS2-Ga2S3 glasses can dissolve relatively large amounts of NdCl3 and Nd2O3 (less than or equal to 3 mol%) and still form stable glasses. They are optically transparent in the range from 19000 cm(-1) to 800 cm(-1). The glass transition temperature (T-g congruent to 378 degrees C) and the glass-forming criteria are only slightly changed by Nd doping (Delta T = 147 degrees C,H-r = 0.78; H' = 0.39, S = 4.10 K, where Delta T = T-c - T-g, H-r is Hruby's criterion, H-r = (T-c - T-g)/(T-m - T-c), H' = (T-c - T-g)/T-g, and S = (T-c - T-x)(T-c - T-g)/T-g). The short-wavelength absorption edge lies near 2.7 eV, doping with Nd creates new absorption bands which can be assigned to electron transfer from the I-4(9/2) level to (4)G(7/2), (4)G(9/2), K-2(13/2),2G(5/2), (2)G(7/2), H-2(11/2), F-4(9/2), F-4(7/2), S-4(3/2), H-2(9/2), F-4(5/2), F-4(3/2), I-4(15/2), I-4(13/2) and I-4(11/2) levels. In doped glasses, several broad luminescence bands, near 910, 1080 and 1360 nm, were found, which can be assigned to the transitions from F-4(3/2) to I-4(9/2), to I-4(11/2) and to I-4(13/2) electron levels. The long-wavelength absorption edge was found near 1000 cm(-1) and is due to multiphonon Ge-S and Ga-S vibrations.