1993 Fiscal Year Final Research Report Summary
Desighn and Development of Infrared-to-Visible Upconversion Rare Earth Laser
| Project/Area Number |
04453069
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| Research Category |
Grant-in-Aid for General Scientific Research (B)
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| Allocation Type | Single-year Grants |
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| Research Field |
無機工業化学・無機材料工学
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| Research Institution | KYOTO UNIVERSITY |
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Principal Investigator |
SOGA Naohiro Kyoto Univ.Fac.Eng.Professor, 工学部, 教授 (80026179)
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| Co-Investigator(Kenkyū-buntansha) |
TANABE Setsuhisa Kyoto Univ.Fac.Int.Hum.St.Research Assoc., 総合人間学部, 助手 (20222119)
HANADA Teiichi Kyoto Univ.Fac.Int.Hum.St.Assoc.Prof., 総合人間学部, 助教授 (50111935)
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| Project Period (FY) |
1992 – 1993
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| Keywords | Rare earth glass / upconversion / Frequency conversion laser / Energy transfer / Excited state absorption / Phonon sideband / Mossbauer effect / Ligand field |
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| Research Abstract |
We have obtained several research results listed below.
It was possible for the first time to ovserve efficient visible upconverion in Er^<3+> doped heavy metal oxide glasses by 800nm radiation of infrared AlGaAs laser diode.
The upconversion efficiency was found to vary with the phonon energy coupled with the rare earth ions in the host glass, which was observed in the phonon sideband spectra.
The Tm^<3+> doped glasses exhibit uv and blue upconversion by 650nm pumping of DCM-dye laser. The main mechanism of Tm^<3+> upconversions was excited state absorption from two kinds of excited levels.
Teh controlling factors of Judd-Ofelt intensity parameters were made clear for Er^<3+> and Nd^<3+> ions in oxide and several fluoride glasses. Among three OMEGA_t parameters, the OMEGA_6 showed a strong correlation between the ^<151>Eu isomer shift in Mossbauer effect measurement for the glass with the same composition. These phenomena could be well explained by the shielding effect on the 5dorbital by the 6s electron, the density of which is increased by the covalency effect of rare earth and ligand bond.
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