Electron-lattice coupling parameters and oscillator strengths of cerium-doped lutetium oxyorthosilicate

Journal Article · Mon May 01 00:00:00 EDT 2000 · Physical Review. B, Condensed Matter and Materials Physics

DOI:https://doi.org/10.1103/PhysRevB.61.11973· OSTI ID:20216413

Cooke, D W ^[1]; Bennett, B L ^[1]; McClellan, K J ^[1]; Roper, J M ^[1]; Whittaker, M T ^[1]; Portis, A M ^[2]

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1. Materials Science and Technology Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)
2. Department of Physics, University of California, Berkeley, California 94720-7300 (United States)

Optical absorption of single-crystal, cerium-doped lutetium oxyorthosilicate has been carefully measured in the temperature interval 10-300 K. Prominent Gaussian absorption peaks occur at 3.432{+-}0.002 eV (peak a), 3.502{+-}0.002 eV (peak b), 4.236{+-}0.0002 eV (peak c), and 4.746{+-}0.0002 eV (peak d), in excellent agreement with previously reported excitation spectra. The second moments are well described by the usual linear model, yielding the Huang-Rhys parameter (S) and vibrational quantum energies for the individual peaks. All absorption bands are characterized by S>5 indicating strong coupling between the Ce{sup 3+} ion and lattice. Temperature dependence of the band centroids exhibits contrasting behavior that is dominated by higher-order coupling terms in the linear harmonic oscillator model or by crystal-field effects. Oscillator strengths of the 4f{yields}5d transitions are calculated from Smakula's formula and knowledge of the Ce{sup 3+} distribution between the two crystallographically inequivalent sites. Values for peaks b, c, and d range from approximately 0.003 to 0.004, and peak a spans magnitude approximately 0.012 to 0.018. From the known correlation between average Ce{sup 3+}-ion-ligand distance and oscillator strength, we tentatively conclude that peak a is correlated with the seven-oxygen-coordinated site, and peaks b, c, and d are associated with the six-oxygen-coordinated site. These results support the previously proposed two-activation-center model and identify the centers as the two crystallographically inequivalent substitutional sites. (c) 2000 The American Physical Society.

• OSTI ID: 20216413
• Journal Information: Physical Review. B, Condensed Matter and Materials Physics, Vol. 61, Issue 18; Other Information: PBD: 1 May 2000; ISSN 1098-0121
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CERIUM IONS
LUTETIUM SILICIDES
LUTETIUM OXIDES
HARMONIC OSCILLATOR MODELS
ABSORPTION SPECTRA
OSCILLATOR STRENGTHS
VISIBLE SPECTRA
TEMPERATURE RANGE 0000-0013 K
TEMPERATURE RANGE 0013-0065 K
TEMPERATURE RANGE 0065-0273 K
ELECTRON-PHONON COUPLING
CRYSTAL FIELD
IMPURITIES
EXPERIMENTAL DATA
THEORETICAL DATA