Results 241 to 250 of about 69,985 (292)

Color center and radiation center in Lu2SiO5:Ce crystal

Journal of Rare Earths, 2008
Radiation damage of Lu2SiO5:Ce (LSO:Ce) crystals was investigated through intense UV light. An absorption band at 435 nm was observed in the transmission spectrum of the damaged LSO:Ce crystal, similar to that of absorption band caused by gamma ray irradiation.
Laishun QIN, Shen LU, Dongzhou DING, Huanying LI, Guohao REN   +4 more
openaire   +1 more source

The boron center: A new luminescent center in ZnS crystals

Journal of Luminescence, 1979
Abstract In ZnS crystals containing B, insensitivity of the emission to high pressure, the structure of the excitation spectra and the observed absence of the photo-excited EPR signals suggest that the luminescence may be due to a localized transition between closely associated B Zn and V Zn .
P. Jaszczyn-Kopec, H.D. Fair, D.S. Downs
openaire   +1 more source

Color Centers in Irradiated Durene Crystals

Physica Status Solidi (a), 1981
The optical absorption spectra of γ-irradiated durene single crystals at 77 K are measured using light polarized along the a-, b-, and c′-axes of crystals. In the shorter wavelength region five strong absorption bands are detected. At longer wavelength weak bands at 489 nm with well desolved vibrational structures and relatively broad weak bands at 570
openaire   +1 more source

Impurity centers in ZnSe:Na crystals

Journal of Luminescence, 2011
Abstract The influence of sodium impurity on photoluminescence (PL) spectra of ZnSe crystals doped in a growth process from a Se+Na melt is investigated. It is shown that the introduction of the impurity results in emergence of emission bands in the PL spectra due to the recombination of exciton impurity complexes associated with both donors and ...
G.V. Colibaba, D.D. Nedeoglo, V.V. Ursaki   +2 more
openaire   +1 more source

A model of photogalvanic centers in crystals

Ferroelectrics, 1982
A photogalvanic complex consisting of two neighboring point defects is considered. One of them is a substitution impurity and is described by Lucovsky potential, the second is a Coulomb center (a compensating impurity or vacancy). The contribution of an individual complex to the photogalvanic tensor βijk and the absorption coefficient α has been found.
V. V. Obukhovsky, A. V. Stoyanov
openaire   +1 more source

F_2^− color centers in LiF crystals

Applied Optics, 1986
Methode d'irradiation gamma pour faire des concentration de centres colores F 2 − utiles pour des applications ...
Y Y, Teng, C A, Carey, J D, Kuppenheimer, J C, Doherty   +3 more
openaire   +2 more sources

Luminescence Centers in Crystals

1976
Investigation of the Spectral-Luminescence Properties of Ruby as Active Laser Medium.- I. Spectral Distribution of Luminescence Quantum Efficiency and Absorption Spectra.- II. Phosphorescence of Ruby. Energy Band Scheme.- III. Color Centers in Ruby.- IV.
openaire   +1 more source

Crystal field of octahedral Yb3+ centers in a CsCaF3 crystal

Physics of the Solid State, 1997
The phenomenological crystal-field potentials of cubic and trigonal Yb3+ centers in a CsCaF3 crystal have been determined from the experimental energy-level schemes. These potentials are compared with the potentials of the analogous centers in the isomorphic hosts KMgF3 and KZnF3.
Bespalov V., Kazakov B., Leushin A., Safiullin G.   +3 more
openaire   +3 more sources

Design centering of a GaN photonic crystal nanobeam

2015 17th International Conference on Transparent Optical Networks (ICTON), 2015
It is well known that structures containing photonic crystal cavities produce cavity modes with extremely large Q-factors. This type of structure can be hyper sensitive to both design and manufacturing processes. Each parameter, be it structural or material will have a tolerance associated with it and the purpose of design centering is to obtain a ...
Jonathan R. Pugh, Martin J. Cryan
openaire   +1 more source

Colored Centers in Ionic Crystals

2000
When a vacancy is created in a crystal, an electron may be trapped at this location. This bound electron can absorb light at well defined frequencies, thus changing the color of the crystal.
Jean-Louis Basdevant, Jean Dalibard
openaire   +1 more source