Sm3+ Doped Borotellurite Glass: Absorption, Fluorescence  and Optical Parameters

Borotellurite glasses doped with Sm3+ ions were prepared by a melt–quenching technique. The studies on optical characterization of Sm3+ ions have been carried out through absorption, emission and decay spectra. Judd-Ofelt (JO) intensity analysis has been presented and JO parameters were calculated for Sm3+ ions in borotellurite glasses. Radiative properties such as transition probabilities, branching ratios, radiative lifetime of 4G5/2 level and quantum efficiency were estimated by using JO parameters.

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Synthesis, Structural and Luminescence Studies of Europium Doped Borate Glasses

Journal of Materials and Applications ◽

10.32732/jma.2020.9.1.9 ◽

2020 ◽

Vol 9 (1) ◽

pp. 9-16

Author(s):

V L Usharani ◽

B Eraiah

Keyword(s):

Cross Sections ◽

Transition Probabilities ◽

Emission Cross Section ◽

Radiative Lifetime ◽

Emission Spectra ◽

Optical Gain ◽

Stimulated Emission ◽

Melt Quenching ◽

Fibre Amplifiers ◽

Quenching Method

Different concentration of (0.1, 0.2, 0.3, 0.4, 0.5, 1.0 & 1.5) mol% of europium doped lead borate lithium glasses were prepared by melt quenching method. The properties of thermal, photoluminescence & structural were analyzed using DTA, FTIR and emission spectra. Emission spectra was used to evaluate the Judd-Ofelt (JO) parameters. Radiative parameters like stimulated emission cross-sections (σe), effective band width (∆λeff), transition probabilities (A), optical gain bandwidths (σe x ∆λeff), radiative lifetime (τrad) and optical gain (σe x τrad) values were evaluated for the transition 5D0→7Fj (j=1, 2, 3 and 4) of Eu3+ ions. The outcome of transition 5D0→7F4 at its highest value of branching ratios and stimulated emission cross-section are evaluated with the literature. Hence we can could the prepared host glass doped with Eu3+ ions are good fibre amplifiers and it can be used as a red laser.

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Optical properties of Eu3+ ions in boro-tellurite glass

Communications in Physics ◽

10.15625/0868-3166/26/1/7916 ◽

2016 ◽

Vol 26 (1) ◽

pp. 25

Author(s):

Ngo Van Tam ◽

Vu Phi Tuyen ◽

Phan Van Do

Keyword(s):

Cross Sections ◽

Tellurite Glass ◽

Transition Probabilities ◽

Emission Spectra ◽

Branching Ratios ◽

Stimulated Emission ◽

Radiative Properties ◽

Phonon Coupling ◽

Intensity Parameters ◽

Electron Phonon Coupling

The excitation, emission spectra and and lifetime of Eu-doped borotellurite glasses (BTe) have been investigated. The sideband phonon energy and electron-phonon coupling strength (g) have been found. The intensity parameters Ωλ were calculated from the emission spectrum. These parameters were used to predict radiative properties such as transition probabilities (AR), calculated branching ratios (βR) and stimulated emission cross-sections (σλp) for 5D0→7HJHFJ transitions.

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On the radiative forcing of volcanic plumes: modelling the impact of Mount Etna in the Mediterranean

Annals of Geophysics ◽

10.4401/ag-6879 ◽

2015 ◽

Vol 58 ◽

Author(s):

Pasquale Sellitto ◽

Pierre Briole

Keyword(s):

Radiative Forcing ◽

Optical Characterization ◽

Mount Etna ◽

Asymmetry Factor ◽

Optical Parameters ◽

Aerosol Layer ◽

Volcanic Plumes ◽

The Mediterranean ◽

The Impact

The impact of small to moderate volcanic eruptions on the regional to global radiative forcing and climate is still largely unknown and thought to be presently underestimated. In this work, daily average shortwave radiative forcing efficiencies at the surface (RFEdSurf), at top of the atmosphere (RFEdTOA) and their ratio (f), for upper tropospheric volcanic plumes with different optical characterization, are derived using the radiative transfer model UVSPEC and the LibRadtran suite. The optical parameters of the simulated aerosol layer, i.e., the Ångströem coefficient (alpha), the single scattering albedo (SSA) and the asymmetry factor (g), have been varied to mimic volcanic ash (bigger and more absorbing particles), sulphate aerosols (smaller and more reflective particles) and intermediate/mixed conditions. The characterization of the plume and its vertical distribution have been set-up to simulate Mount Etna, basing on previous studies. The radiative forcing and in particular the f ratio is strongly affected by the SSA and g, and to a smaller extent by alpha, especially for sulphates-dominated plumes. The impact of the altitude and thickness of the plume on the radiative forcing, for a fixed optical characterization of the aerosol layer, has been found negligible (less than 1% for RFEdSurf, RFEdTOA and f). The simultaneous presence of boundary layer/lower tropospheric marine or dust aerosols, like expected in the Mediterranean area, modulates only slightly (up to 12 and 14% for RFEdSurf and RFEdTOA, and 3 to 4% of the f ratio) the radiative effects of the upper tropospheric volcanic layer.

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Optical Properties of Alloyed PbSexS1-x Nanorods

MRS Proceedings ◽

10.1557/opl.2012.721 ◽

2012 ◽

Vol 1390 ◽

Author(s):

Anna Rubin Brusilovski ◽

Dikla Kolan ◽

Georgy I. Maikov ◽

Roman Vaxenburg ◽

Aldona Sashchiuk ◽

...

Keyword(s):

Radiative Lifetime ◽

Optical Characterization ◽

Band Edge ◽

Cryogenic Temperatures ◽

Photoluminescence Spectra ◽

Absorption Band Edge ◽

Electron Hole ◽

Small Band ◽

Degenerate Band Edge

ABSTRACTWe report the synthesis, structural and optical characterization of PbSexS1-x nanorods with diameter between 2 nm to 4.5 nm and length of 12 nm to 24 nm. Their typical photoluminescence spectra exhibit a split of the band-edge exciton band. The temperature dependence photoluminescence of these nanorods revealed a relatively small band-gap temperature coefficient and a mild extension of the radiative lifetime at cryogenic temperatures - all in comparison with photoluminescence processes in PbSe nanorods, as well as in PbSexS1-x quantum dots, with similar absorption band-edge energy. A theoretical model associates the experimental observations to the occurrence of independent transitions from either degenerate or non-degenerate band-edge valleys in PbSexS1-x nanorods, each of which possessing a relatively small electron-hole exchange interaction.

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Radiative properties of Eu(DBM)3Phen-doped poly(methyl methacrylate)

Journal of Materials Research ◽

10.1557/jmr.2003.0265 ◽

2003 ◽

Vol 18 (8) ◽

pp. 1895-1899 ◽

Cited By ~ 28

Author(s):

Hao Liang ◽

Zhiqiang Zheng ◽

Qijin Zhang ◽

Hai Ming ◽

Biao Chen ◽

...

Keyword(s):

Methyl Methacrylate ◽

Transition Probabilities ◽

Emission Cross Section ◽

Radiative Lifetime ◽

Fluorescence Emission ◽

Emission Spectra ◽

Radiative Properties ◽

Fluorescence Intensity Ratio ◽

Fluorescence Emission Spectra ◽

Poly Methyl Methacrylate

Eu(DBM)3Phen-doped poly(methyl methacrylate) (PMMA) with different doping concentrations was prepared. Judd–Ofelt parameters Ω2 and Ω4 and the fluorescence intensity ratio R were computed from the fluorescence emission spectra and were analyzed. The radiative properties, such as transition probabilities, emission cross section (46.47 × 10−22 cm2), fluorescence branching ratios (90.34%), and radiative lifetime (1.704 ms), reveal that Eu(DBM)3 Phen-doped PMMA has potential use as a laser material.

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