Effects of Gamma-Irradiation and Ion Implantation in Chalcogenide Glasses

Long-term radiation-induced optical darkening effects in chalcogenide glasses

“…In spite of the long-term radiation-induced optical darkening effects detected in this study for both investigated g-As 2 S 3 and g-Ge 15.8 As 21 S 63.2 , the mechanisms of long-term radiation-induced structural changes in these compounds are found to be different [2,11,13,14]. It is concluded from the recent positron annihilation spectroscopy measurements with the Doppler broadening of annihilation line (DBAL) technique [11,14].…”

“…Indeed, on the one hand, the established for As-S based glasses the long-term radiation-induced structural changes in DBAL data [2,11,14], when the first sharp diffraction peak (FSDP) becomes weaker and broader after γ-irradiation [2,12], have been interpreted within the non-defective distortion model. Since the FSDP originates as a signature of the medium-range order (MRO) structure within the range 5…20 Å in covalent glasses (for review, see [18]), which is commonly accepted by many researchers in literature, the FSDP weakening and broadening means the decrease in the MRO structural correlation length and, consequently, the rise of disordering on the MRO scale.…”

“…Thus, when the radiation-induced structural changes in ChGs occur towards the disordering on the MRO scale and no changes or ordering on the SRO scale, the non-defective mechanism in the frame of the distortion model and any other models (if exist), resulting in a final structural configuration without charged defects, is dominant. On the other hand, the established for Ge-S based glasses the long-term radiation-induced structural changes in DBAL data [2,11,14], when the FSDP remains practically unchanged [2] or its intensity can be something higher [16] and peak is probably something narrower upon γ-irradiation, have been interpreted within the defective CTD model, involving atomic rearrangements directly in the first coordination shells (first-nearest-neighbor atomic correlations), that is, on the SRO scale. The unobservable changes in the FSDP and/or the FSDP sharping and narrowing means that no changes or increasing the MRO structural correlation length and, consequently, a stable MRO structure and/or rise of ordering on the MRO scale take place.…”

“…It may also indicate that a backward measuring chronology mentioned by the authors [10], it is not necessary to be performed, being although useful to make in situ experiment, as the radiation-induced optical darkening effects in chalcogenide glasses are stable in time, and corresponding radiation-induced structural changes can be correctly investigated with a long-time interval. In this respect, the long-term radiation-induced structural changes examined in the works [2,[11][12][13][14] are very important in view of practical applications of chalcogenide glasses. In particular, the long-term radiation-induced effects demonstrate the possibilities for development of innovative chalcogenide glass based longterm dosimeter systems with stable and controlled parameters.…”

“…Radiation-induced optical effects (RIOEs) caused by 60 Co γ-irradiation in chalcogenide glasses (ChGs) are well-known to be used for dosimetric applications [1,2]. RIOEs could be also considered as the main control parameter of radiation sensitivity of ChGs.…”