Characterization of radiation-induced effects in amorphous arsenic sulfides by positron annihilation lifetime spectroscopy. Issue 9 (27th January 2015)

• Record Type: Journal Article
• Authors: Shpotyuk, Mykhaylo; Ingram, Adam; Shpotyuk, Oleh
• Is Part Of: Journal of materials research. Volume 30:Issue 9(2015)
• Page Start: 1422
• Page End: 1429
• Publication Date: 2015-01-27
• Subjects: radiation effects, -- amorphous, -- defects; Materials -- Research -- Periodicals; 620.1105
• DOI: 10.1557/jmr.2014.372
• Languages: English
• ISSNs: 0884-2914

Abstract

Abstract: Abstract : Positron annihilation lifetime spectroscopy is used to study the structural changes in amorphous arsenic sulfides of a binary As–S system induced by high-energy γ-radiation of 60 Co source. It is demonstrated that radiation-induced effects in positron trapping modes of the studied glasses are in strict correlation with shift of their fundamental optical absorption edge. The γ-induced physical aging is shown to be dominated in the rejuvenated S-rich glasses, thermally induced physical aging accompanies annealing of the rejuvenated g-As x S100− x, while coordination topological defects are character for near-stoichiometric glasses (both annealed and rejuvenated). The competitive processes of free-volume void evolutions such as agglomeration–fragmentation, expansion–contraction, and charging–discharging are considered as possible stages of radiation- and thermally induced structural transformations. The meaningful model for γ-irradiation and relaxation-driven evolution in the void structure of As–S glasses is proposed. The free-volume evolution in g-As x S100− x associated with thermally and γ-induced physical aging is shown to be consistent with a void fragmentation process, while the formation of γ-induced coordination topological defects leads mainly to void charging.