Ionizing-radiation effects in lanthanum magnesium aluminate crystals

Journal Article · Sun Oct 15 00:00:00 EDT 1989 · Physical Review (Section) B: Condensed Matter; (USA)

DOI:https://doi.org/10.1103/PhysRevB.40.8522· OSTI ID:5371072

Chen, C Y; Park, J L ^[1]; Cain, L S ^[2]; Pogatshnik, G J ^[3]; Kokta, M R ^[4]

---

1. Solid State Division, Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, Tennessee 37831-6032 (US)
2. Solid State Division, Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, Tennessee 37831-6032 and Department of Physics, Davidson College, Davidson, North Carolina 28036
3. Department of Physics, Southern Illinois University, Edwardsville, Illinois 62026-1654
4. Union Carbide Corporation, Washougal, Washington 98671

Optical and electron-paramagnetic-resonance (EPR) techniques are used to study the effects of {gamma} and electron irradiation on undoped lanthanum magnesium aluminate crystals. It has been shown that room-temperature irradiation produces a strong optical-absorption band at 400 nm associated with trapped-hole centers (J. Solid State Chem. 61, 67 (1986)). The absorption band produced by the presence of this hole center is anisotropic with a preferential polarization anisotropy for {bold E}{perpendicular}{ital c} and the oscillator strength is found to be 0.07{plus minus}0.02. The optical-absorption band can be bleached at 295 and 77 K, indicating that the excited states of the holes are close to the valence band. Polarized bleaching experiments failed to show any linear dichroism, indicating that the holes are not strongly localized at a single oxygen site. Irradiation at 77 K produces additional electron and hole centers which are presumably associated with the aluminum cations.

• DOE Contract Number: AC05-84OR21400
• OSTI ID: 5371072
• Journal Information: Physical Review (Section) B: Condensed Matter; (USA), Vol. 40:12; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
LANTHANUM COMPOUNDS
PHYSICAL RADIATION EFFECTS
MAGNESIUM COMPOUNDS
ABSORPTION SPECTRA
ALUMINATES
ELECTRON COLLISIONS
ELECTRON SPIN RESONANCE
GAMMA RADIATION
LASER MATERIALS
OPTICAL PROPERTIES
ALKALINE EARTH METAL COMPOUNDS
ALUMINIUM COMPOUNDS
COLLISIONS
ELECTROMAGNETIC RADIATION
IONIZING RADIATIONS
MAGNETIC RESONANCE
MATERIALS
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
RADIATION EFFECTS
RADIATIONS
RARE EARTH COMPOUNDS
RESONANCE
SPECTRA
360605* - Materials- Radiation Effects