Radiation induced formation of color centers in PbWO4 single crystals

1997 ◽  
Vol 82 (11) ◽  
pp. 5758-5762 ◽  
Author(s):  
M. Nikl ◽  
K. Nitsch ◽  
S. Baccaro ◽  
A. Cecilia ◽  
M. Montecchi ◽  
...  
Keyword(s):  
Single Crystals ◽  
Color Centers ◽  
Radiation Induced

Annealing of radiation-induced defects in ion-implanted AIIBVI single crystals

1989 ◽  
Vol 32 (3) ◽  
pp. 198-203
Author(s):  
A. N. Georgobiani ◽  
M. B. Kotlyarevskii ◽  
B. P. Dement'ev ◽  
V. N. Mikhalenko ◽  
N. V. Serdyuk ◽  
...  
Keyword(s):  
Single Crystals ◽  
Radiation Induced ◽  
Induced Defects ◽  
Ion Implanted

scholarly journals Continuous wave ultraviolet radiation induced frustration of etching in lithium niobate single crystals

2003 ◽  
Vol 206 (1-4) ◽  
pp. 46-52 ◽  
Author(s):  
S. Mailis ◽  
C. Riziotis ◽  
P.G.R. Smith ◽  
J.G. Scott ◽  
R.W. Eason
Keyword(s):  
Lithium Niobate ◽  
Ultraviolet Radiation ◽  
Single Crystals ◽  
Continuous Wave ◽  
Radiation Induced

Color centers in LiCaAlF6 single crystals and their suppression by doping

2002 ◽  
Vol 91 (9) ◽  
pp. 5666-5670 ◽  
Author(s):  
Hiroki Sato ◽  
Hiroshi Machida ◽  
Kiyoshi Shimamura ◽  
Amina Bensalah ◽  
Tomohiko Satonaga ◽  
...  
Keyword(s):  
Single Crystals ◽  
Color Centers

scholarly journals Глубокие центры радиационных дефектов в монокристаллах CdZnTe, созданные потоком быстрых нейтронов

2018 ◽  
Vol 52 (3) ◽  
pp. 322 ◽  
Author(s):  
С.В. Пляцко ◽  
Л.В. Рашковецкий
Keyword(s):  
Activation Energy ◽  
Neutron Flux ◽  
Fast Neutron ◽  
Single Crystals ◽  
Isothermal Annealing ◽  
Fast Neutron Flux ◽  
Photoluminescence Properties ◽  
Radiation Induced ◽  
Induced Defects

AbstractThe effect of a fast neutron flux (Φ = 10^14–10^15 cm^–2) on the electrical and photoluminescence properties of p -CdZnTe single crystals is studied. Isothermal annealing is performed ( T = 400–500 K), and the activation energy of the dissociation of radiation-induced defects is determined at E _D ≈ 0.75 eV.

Radiation-induced defects in montebrasite: An electron paramagnetic resonance study of O – hole and Ti3+ electron centers

2020 ◽  
Vol 105 (7) ◽  
pp. 1051-1059
Author(s):  
José R. Toledo ◽  
Raphaela de Oliveira ◽  
Lorena N. Dias ◽  
Mário L.C. Chaves ◽  
Joachim Karfunkel ◽  
...  
Keyword(s):  
Electron Paramagnetic Resonance ◽  
Electron Irradiation ◽  
Color Centers ◽  
Hydroxyl Groups ◽  
Γ Irradiation ◽  
Paramagnetic Resonance ◽  
Radiation Induced ◽  
Induced Defects ◽  
Electron Paramagnetic ◽  
Hole Centers

Abstract Montebrasite is a lithium aluminum phosphate mineral with the chemical formula LiAlPO4(Fx,OH1–x) and considered a rare gemstone material when exhibiting good crystallinity. In general, montebrasite is colorless, sometimes pale yellow or pale blue. Many minerals that do not have colors contain hydroxyl ions in their crystal structures and can develop color centers after ionization or particle irradiation, examples of which are topaz, quartz, and tourmaline. The color centers in these minerals are often related to O− hole centers, where the color is produced by bound small polarons inducing absorption bands in the near UV to the visible spectral range. In this work, colorless montebrasite specimens from Minas Gerais state, Brazil, were investigated by electron paramagnetic resonance (EPR) for radiation-induced defects and color centers. Although γ irradiation (up to a total dose of 1 MGy) did not visibly modify color, a 10 MeV electron irradiation (80 MGy) induced a pale greenish-blue color. Using EPR, O− hole centers were identified in both γ- or electron-irradiated montebrasite samples showing superhyperfine interactions with two nearly equivalent 27Al nuclei. In addition, two different Ti3+ electron centers were also observed. From the γ irradiation dose dependency and thermal stability experiments, it is concluded that production of O− hole centers is limited by simultaneous creation of Ti3+ electron centers located between two equivalent hydroxyl groups. In contrast, the concentration of O− hole centers can be strongly increased by high-dose electron irradiation independent of the type of Ti3+ electron centers. From detailed analysis of the EPR angular rotation patterns, microscopic models for the O− hole and Ti3+ electron centers are presented, as well as their role in the formation of color centers discussed and compared to other minerals.

Luminescence of color centers in α-Al2O3 single crystals

1995 ◽  
Vol 62 (3) ◽  
pp. 585-588 ◽  
Author(s):  
V. V. Arutyunyan ◽  
A. K. Babayan ◽  
A. N. Belskii ◽  
V. A. Gevorkyan ◽  
V. N. Makhov ◽  
...  
Keyword(s):  
Single Crystals ◽  
Color Centers ◽  
Α Al2o3

Luminescence and radiation-induced color centers in anion-defective alumina crystals after high-dose irradiation

2016 ◽  
Vol 90 ◽  
pp. 90-93 ◽  
Author(s):  
V.S. Kortov ◽  
V.A. Pustovarov ◽  
S.V. Zvonarev ◽  
T.V. Shtang
Keyword(s):  
Color Centers ◽  
High Dose ◽  
Dose Irradiation ◽  
Radiation Induced

Positron capture by color centers in single crystals

1972 ◽  
Vol 39 (5) ◽  
pp. 381-382 ◽  
Author(s):  
K.P. Arefiev ◽  
S.A. Vorobiev
Keyword(s):  
Single Crystals ◽  
Color Centers ◽  
Positron Capture

scholarly journals Atomic, electronic and magnetic structure of an oxygen interstitial in neutron-irradiated Al2O3 single crystals

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
V. Seeman ◽  
A. Lushchik ◽  
E. Shablonin ◽  
G. Prieditis ◽  
D. Gryaznov ◽  
...  
Keyword(s):  
Dft Calculations ◽  
Single Crystals ◽  
Density Functional ◽  
Magnetic Moments ◽  
Atomic Charges ◽  
Interstitial Oxygen ◽  
Absorption Bands ◽  
Magnetic Field Rotation ◽  
Formal Charge ◽  
Radiation Induced

Abstract A single radiation-induced superoxide ion $$O_{2}^{ - }$$ O 2 - has been observed for the first time in metal oxides. This structural defect has been revealed in fast-neutron-irradiated (6.9×1018n/cm2) corundum (α-Al2O3) single crystals using the EPR method. Based on the angular dependence of the EPR lines at the magnetic field rotation in different planes and the determined g tensor components, it is shown that this hole-type $$O_{2}^{ - }$$ O 2 - center (i) incorporates one regular and one interstitial oxygen atoms being stabilized by a trapped hole (S = 1/2), (ii) occupies one oxygen site in the (0001) plane being oriented along the a axis, and (iii) does not contain any other imperfection/defect in its immediate vicinity. The thermal stepwise annealing (observed via the EPR signal and corresponding optical absorption bands) of the $$O_{2}^{ - }$$ O 2 - centers, caused by their destruction with release of a mobile ion (tentatively the oxygen ion with the formal charge −1), occurs at 500–750 K, simultaneously with the partial decay of single F-type centers (mostly with the EPR-active F+ centers). The obtained experimental results are in line with the superoxide defect configurations obtained via density functional theory (DFT) calculations employing the hybrid B3PW exchange-correlation functional. In particular, the DFT calculations confirm the $$O_{2}^{ - }$$ O 2 - center spin S = 1/2, its orientation along the a axis. The $$O_{2}^{ - }$$ O 2 - center is characterized by a short O–O bond length of 1.34 Å and different atomic charges and magnetic moments of the two oxygens. We emphasize the important role of atomic charges and magnetic moments analysis in order to identify the ground state configuration.

Sign in / Sign up

Export Citation Format

Share Document