Upconversion properties, multiphonon relaxation, and local environment of rare-earth ions in fluorophosphate glasses

Journal Article · Sun Mar 01 04:00:00 EST 1992 · Physical Review, B: Condensed Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.45.4620· OSTI ID:7047712

Tanabe, S ^[1]; Yoshii, S; Hirao, K; Soga, N ^[2]

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1. Department of Chemistry, College of Liberal Arts and Sciences, Kyoto University, Sakyo-ku, Kyoto 606-01 (Japan)
2. Department of Industrial Chemistry, Faculty of Engineering, Kyoto University, Sakyo-ku, Kyoto 606-01 (Japan)

The upconversion properties of Er{sup 3+} ions were studied for the fluorophosphate glasses (45{minus}{ital x})AlF{sub 3}{center dot}{ital x}AlPO{sub 4}{center dot}5ErF{sub 3}{center dot}30CaF{sub 2}{center dot}20BaF{sub 2}, with use of the infrared radiation from a (Ga,Al)As laser diode ({lambda}=802 nm) as an excitation source. Green upconversion fluorescence due to the {sup 4}{ital S}{sub 3/2}{r arrow}{sup 4}{ital I}{sub 15/2} transition could be observed for the fluoride glass, while the fluorescence intensity for fluorophosphate glasses decreased drastically with increasing AlPO{sub 4} content. It was found from the phonon sideband spectra of Eu{sup 3+} that the phonon with {h bar}{omega}=1060 cm{sup {minus}1}, corresponding to P-O{sup {minus}} stretching vibrations, became coupled to the multiphonon relaxation of rare-earth ions, and its electron-phonon coupling strength increased greatly with increasing phosphate content. The temperature dependence of upconversion intensity was large for the fluoride system, while it was small for the fluorophosphate system. These tendencies could be well explained by considering the multiphonon decay rate of the Er{sup 3+} intermediate level and its temperature dependence, which are functions of the phonon energy of the host and the energy gap to the next-lower level of Er{sup 3+}. Combined with the results of {sup 151}Eu Moessbauer spectroscopy, it was concluded that the upconversion properties in these glasses were largely influenced by the local structure and the phonon mode coupled to the rare-earth ions.

• OSTI ID: 7047712
• Journal Information: Physical Review, B: Condensed Matter; (United States), Journal Name: Physical Review, B: Condensed Matter; (United States) Vol. 45:9; ISSN 0163-1829; ISSN PRBMD
• Country of Publication: United States
• Language: English

Related Subjects

664200* -- Spectra of Atoms & Molecules & their Interactions with Photons-- (1992-)
74 ATOMIC AND MOLECULAR PHYSICS
ALLOYS
CHARGED PARTICLES
ELECTROMAGNETIC RADIATION
ERBIUM ADDITIONS
ERBIUM ALLOYS
EUROPIUM 151
EUROPIUM ISOTOPES
FLUORESCENCE
GLASS
INFRARED RADIATION
INTERMEDIATE MASS NUCLEI
IONS
ISOTOPES
LATTICE VIBRATIONS
LUMINESCENCE
MOESSBAUER EFFECT
MULTICHARGED IONS
NUCLEI
ODD-EVEN NUCLEI
PHOSPHATE GLASS
RADIATIONS
RARE EARTH ADDITIONS
RARE EARTH ALLOYS
RARE EARTH ISOTOPES
RARE EARTH NUCLEI
RELAXATION
STABLE ISOTOPES