Generation of [ital E][prime] centers and oxygen hole centers in synthetic silica glasses by [gamma] irradiation

Journal Article · Sun Aug 01 00:00:00 EDT 1993 · Physical Review, B: Condensed Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.48.3116· OSTI ID:5430111

Imai, H; Arai, K ^[1]; Isoya, J ^[2]; Hosono, H; Abe, Y ^[3]; Imagawa, H ^[4]

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1. Electrotechnical Laboratory, 1-1-4 Umezono, Tsukuba-shi, Ibaraki 305 (Japan)
2. University of Library and Information Science, 1-2 Kasuga, Tsukuba-shi, Ibaraki 305 (Japan)
3. Nagoya Institute of Technology, Gokiso, Showa-ku, Nagoya-shi, Aichi 466 (Japan)
4. Toyo University, 2100 Kujirainakanodai, Kawagoe-shi, Saitama 350 (Japan)

Generation of typical paramagnetic centers by [gamma] irradiation was studied for various kinds of synthetic silica glasses. Growth behavior of [ital E][prime] centers and nonbridging oxygen hole centers (NBOHC's) with [gamma]-ray dose depends on contained preexisting point defects. By irradiation at room temperature, [ital E][prime] centers grow linearly and show a saturating tendency in silicas that contain precursors for [ital E][prime] centers, such as oxygen-deficient centers (ODC's), Si-H bonds or Si-Cl bonds. In silicas that contain very few precursors for [ital E][prime] centers, the growth of [ital E][prime] centers with the dose substantially equals that of NBOHC's and both follow a sublinear growth law in which the concentration of the defects is proportional to the square root of the dose. These results lead to the conclusion that [gamma] irradiation fundamentally creates defect pairs of an [ital E][prime] center and an oxygen hole center from an intrinsic Si-O network of amorphous silica; this is in addition to a large amount of [ital E][prime] centers induced from preexisting point defects as precursors. By irradiation at 77 K, [ital E][prime] centers and self-trapped holes are suggested to be formed as the defect pair from the Si-O network, while the conversion of the precursors into [ital E][prime] centers is probably lessened. Concentration of [ital E][prime] centers generated by [gamma] irradiation is almost the same as that of irradiation of ultraviolet lasers and x rays if they are compared based on the absorbed energy. Thus, defect generation with [gamma] rays is suggested to involve similar fundamental processes as those with photons, which have much smaller energy than [gamma] rays.

• OSTI ID: 5430111
• Journal Information: Physical Review, B: Condensed Matter; (United States), Vol. 48:5; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
SILICA
ELECTRON SPIN RESONANCE
POINT DEFECTS
AMBIENT TEMPERATURE
GAMMA RADIATION
GLASS
HOLES
OXYGEN
PHYSICAL RADIATION EFFECTS
VACANCIES
CHALCOGENIDES
CRYSTAL DEFECTS
CRYSTAL STRUCTURE
ELECTROMAGNETIC RADIATION
ELEMENTS
IONIZING RADIATIONS
MAGNETIC RESONANCE
MINERALS
NONMETALS
OXIDE MINERALS
OXIDES
OXYGEN COMPOUNDS
RADIATION EFFECTS
RADIATIONS
RESONANCE
SILICON COMPOUNDS
SILICON OXIDES
360206* - Ceramics
Cermets
& Refractories- Radiation Effects