The Experts below are selected from a list of 70323 Experts worldwide ranked by ideXlab platform

K Annapurna - One of the best experts on this subject based on the ideXlab platform.

  • influence of bismuth on structural elastic and spectroscopic properties of nd3 doped zinc boro bismuthate glasses
    Journal of Luminescence, 2014
    Co-Authors: Gaurav Gupta, Atul D Sontakke, Prantik Karmakar, Kaushik Biswas, S Balaji, R Saha, K Annapurna
    Abstract:

    Abstract The present investigation reports, influence of bismuth addition on structural, elastic and spectral properties of [(99.5− x ) {4ZnO−3B 2 O 3 }−0.5Nd 2 O 3 − x Bi 2 O 3 where x =0, 5, 10, 20, 30, 40, 50 and 60] glasses. The measured FTIR reflectance spectra facilitated a thorough insight of methodical modifications that are arising in the glass structure from borate (build by BO 3 and BO 4 units) to bismuthate (BiO 3 and BiO 6 units) network due to the increase of bismuth content ensuing with a steady decrease in host phonon energy ( ν ph ). The elastic properties estimated from measured longitudinal and shear ultrasonic velocities ( U L and U s ) demonstrated the reduction in network rigidity of glasses on Bi 2 O 3 inclusion. The three phenomenological Judd–Ofelt intensity parameters ( Ω 2, 4, 6 ) were obtained from recorded absorption spectra of Nd 3+ ions in these glasses and have been used to predict radiative properties as a function of variation in bismuth content. The reduced host phonon energy and high optical basicity effect due to Bi 2 O 3 incorporation remarkably improved the Nd 3+ luminescence properties such as Emission intensity, quantum yield and Emission Cross-section. The quantum yield showed a strong increase from mere 16% in Zinc–Borate glass to almost 73% in 60 mol% Bi 2 O 3 containing glass. Similarly, the Emission Cross-section for Nd 3+ 4 F 3/2 → 4 I 11/2 laser transition raised from 2.43×10 −20  cm 2 to 3.95×10 −20  cm 2 in studied concentration suggesting a strong improvement in Nd 3+ laser spectroscopic properties in Zinc–Boro-Bismuthate glass. These materials may be promising for compact solid state infrared lasers.

  • spectroscopic properties and concentration effects on luminescence behavior of nd3 doped zinc boro bismuthate glasses
    Materials Chemistry and Physics, 2013
    Co-Authors: Atul D Sontakke, K Annapurna
    Abstract:

    Abstract A detail investigation on laser spectroscopic properties as a function of Nd 3+ ions concentration in a new heavy metal oxide based Zinc–Boro–Bismuthate glasses is reported. The Judd–Ofelt analysis indicated an enhancement in Nd–O bond covalency as well as the local asymmetry of active ions on increase in dopant concentration from 0.1 to 1.5 mol%. Based on the Judd–Ofelt intensity parameters, several radiative properties such as transition probability, radiative lifetime, branching ratio and stimulated Emission Cross-section of Nd 3+ ions have been derived. The luminescence intensity has showed a strong increase up to 0.5 mol% Nd 2 O 3 , which then attains maximum at 1 mol% and falls down for further increase in dopant concentration. The luminescence quenching behavior at higher dopant concentration has been attributed to the hopping migration assisted energy transfer mechanism leading to the Cross-relaxation among active ions. The energy transfer micro-parameters for Cross-relaxation ( C DA ) and donor energy migration ( C DD ) have been derived from the luminescence decay analysis as well as spectral overlap function respectively. The high stimulated Emission Cross-section and smaller Cross-relaxation micro-parameters along with high quantum yield from the present glasses suggests their potential for compact infrared lasers and waveguide applications.

M I Kupchenko - One of the best experts on this subject based on the ideXlab platform.

  • spectroscopy and continuous wave diode pumped laser action of yb 3 yvo 4
    Optics Letters, 2004
    Co-Authors: V E Kisel, N V Kuleshov, A E Troshin, N A Tolstik, V G Shcherbitsky, V N Matrosov, T A Matrosova, M I Kupchenko
    Abstract:

    The growth, spectroscopic properties, and laser performance of Yb:YVO4 crystal with laser diode pumping are reported. A peak absorption Cross section of 7.4×10-20 cm2 at 985 nm, a radiative lifetime of 0.25 ms, and a stimulated-Emission Cross section of 1.25×10-20 cm2 at 1008 nm for π polarization were determined for the Yb3+ ions in YVO4. Continuous-wave laser action of Yb:YVO4 at 1020–1027 nm was demonstrated with an output power of 610 mW and a slope efficiency of 49%.

  • spectroscopy and continuous wave diode pumped laser action of yb3 yvo4
    Optics Letters, 2004
    Co-Authors: V E Kisel, N V Kuleshov, A E Troshin, N A Tolstik, V G Shcherbitsky, V N Matrosov, T A Matrosova, M I Kupchenko
    Abstract:

    The growth, spectroscopic properties, and laser performance of Yb:YVO4 crystal with laser diode pumping are reported. A peak absorption Cross section of 7.4×10-20 cm2 at 985 nm, a radiative lifetime of 0.25 ms, and a stimulated-Emission Cross section of 1.25×10-20 cm2 at 1008 nm for π polarization were determined for the Yb3+ ions in YVO4. Continuous-wave laser action of Yb:YVO4 at 1020–1027 nm was demonstrated with an output power of 610 mW and a slope efficiency of 49%.

V E Kisel - One of the best experts on this subject based on the ideXlab platform.

  • spectroscopy and continuous wave diode pumped laser action of yb 3 yvo 4
    Optics Letters, 2004
    Co-Authors: V E Kisel, N V Kuleshov, A E Troshin, N A Tolstik, V G Shcherbitsky, V N Matrosov, T A Matrosova, M I Kupchenko
    Abstract:

    The growth, spectroscopic properties, and laser performance of Yb:YVO4 crystal with laser diode pumping are reported. A peak absorption Cross section of 7.4×10-20 cm2 at 985 nm, a radiative lifetime of 0.25 ms, and a stimulated-Emission Cross section of 1.25×10-20 cm2 at 1008 nm for π polarization were determined for the Yb3+ ions in YVO4. Continuous-wave laser action of Yb:YVO4 at 1020–1027 nm was demonstrated with an output power of 610 mW and a slope efficiency of 49%.

  • spectroscopy and continuous wave diode pumped laser action of yb3 yvo4
    Optics Letters, 2004
    Co-Authors: V E Kisel, N V Kuleshov, A E Troshin, N A Tolstik, V G Shcherbitsky, V N Matrosov, T A Matrosova, M I Kupchenko
    Abstract:

    The growth, spectroscopic properties, and laser performance of Yb:YVO4 crystal with laser diode pumping are reported. A peak absorption Cross section of 7.4×10-20 cm2 at 985 nm, a radiative lifetime of 0.25 ms, and a stimulated-Emission Cross section of 1.25×10-20 cm2 at 1008 nm for π polarization were determined for the Yb3+ ions in YVO4. Continuous-wave laser action of Yb:YVO4 at 1020–1027 nm was demonstrated with an output power of 610 mW and a slope efficiency of 49%.

N V Kuleshov - One of the best experts on this subject based on the ideXlab platform.

  • spectral properties of nd3 ions in the new fluoride glasses with small additives of the phosphates
    Journal of Luminescence, 2019
    Co-Authors: E V Kolobkova, Ahmed Alkhlef, B M Dinh, A S Yasukevich, O P Dernovich, N V Kuleshov, N V Nikonorov
    Abstract:

    Abstract A series of the new fluoride glasses with small additives of the phosphates doped with different of Nd3+ content is developed. The dopant concentration dependence of optical absorption and Emission properties is reported here for the concentration range of 2.5×1020 to 1.0×1021 (ions/cm3). Using the Judd-Ofelt theory the phenomenological intensity parameters Ωt (t = 2; 4; 6) were obtained for all glasses studied. Fluorescence lifetime, quantum efficiency and nonlinear refractive index n2. were obtained. The peak stimulated Emission Cross sections of the transitions at 899 nm, 1053 nm and 1320 nm were calculated according to J-O theory. The stimulated Emission Cross-sections of 4F3/2→4I9/2, 4F3/2→4I11/2 and 4F3/2→4I13/2 transitions were determined by the Fuchtbauer-Landenburg equation (FL) and the modified reciprocity method (MR) for all Nd3+concentrations. The analysis of the luminescence quenching depending on the concentration of the activator was carried out. It was concluded that present fluoride glass with small additives of phosphates is a promising material for laser applications.

  • spectroscopy and continuous wave diode pumped laser action of yb 3 yvo 4
    Optics Letters, 2004
    Co-Authors: V E Kisel, N V Kuleshov, A E Troshin, N A Tolstik, V G Shcherbitsky, V N Matrosov, T A Matrosova, M I Kupchenko
    Abstract:

    The growth, spectroscopic properties, and laser performance of Yb:YVO4 crystal with laser diode pumping are reported. A peak absorption Cross section of 7.4×10-20 cm2 at 985 nm, a radiative lifetime of 0.25 ms, and a stimulated-Emission Cross section of 1.25×10-20 cm2 at 1008 nm for π polarization were determined for the Yb3+ ions in YVO4. Continuous-wave laser action of Yb:YVO4 at 1020–1027 nm was demonstrated with an output power of 610 mW and a slope efficiency of 49%.

  • spectroscopy and continuous wave diode pumped laser action of yb3 yvo4
    Optics Letters, 2004
    Co-Authors: V E Kisel, N V Kuleshov, A E Troshin, N A Tolstik, V G Shcherbitsky, V N Matrosov, T A Matrosova, M I Kupchenko
    Abstract:

    The growth, spectroscopic properties, and laser performance of Yb:YVO4 crystal with laser diode pumping are reported. A peak absorption Cross section of 7.4×10-20 cm2 at 985 nm, a radiative lifetime of 0.25 ms, and a stimulated-Emission Cross section of 1.25×10-20 cm2 at 1008 nm for π polarization were determined for the Yb3+ ions in YVO4. Continuous-wave laser action of Yb:YVO4 at 1020–1027 nm was demonstrated with an output power of 610 mW and a slope efficiency of 49%.

Atul D Sontakke - One of the best experts on this subject based on the ideXlab platform.

  • influence of bismuth on structural elastic and spectroscopic properties of nd3 doped zinc boro bismuthate glasses
    Journal of Luminescence, 2014
    Co-Authors: Gaurav Gupta, Atul D Sontakke, Prantik Karmakar, Kaushik Biswas, S Balaji, R Saha, K Annapurna
    Abstract:

    Abstract The present investigation reports, influence of bismuth addition on structural, elastic and spectral properties of [(99.5− x ) {4ZnO−3B 2 O 3 }−0.5Nd 2 O 3 − x Bi 2 O 3 where x =0, 5, 10, 20, 30, 40, 50 and 60] glasses. The measured FTIR reflectance spectra facilitated a thorough insight of methodical modifications that are arising in the glass structure from borate (build by BO 3 and BO 4 units) to bismuthate (BiO 3 and BiO 6 units) network due to the increase of bismuth content ensuing with a steady decrease in host phonon energy ( ν ph ). The elastic properties estimated from measured longitudinal and shear ultrasonic velocities ( U L and U s ) demonstrated the reduction in network rigidity of glasses on Bi 2 O 3 inclusion. The three phenomenological Judd–Ofelt intensity parameters ( Ω 2, 4, 6 ) were obtained from recorded absorption spectra of Nd 3+ ions in these glasses and have been used to predict radiative properties as a function of variation in bismuth content. The reduced host phonon energy and high optical basicity effect due to Bi 2 O 3 incorporation remarkably improved the Nd 3+ luminescence properties such as Emission intensity, quantum yield and Emission Cross-section. The quantum yield showed a strong increase from mere 16% in Zinc–Borate glass to almost 73% in 60 mol% Bi 2 O 3 containing glass. Similarly, the Emission Cross-section for Nd 3+ 4 F 3/2 → 4 I 11/2 laser transition raised from 2.43×10 −20  cm 2 to 3.95×10 −20  cm 2 in studied concentration suggesting a strong improvement in Nd 3+ laser spectroscopic properties in Zinc–Boro-Bismuthate glass. These materials may be promising for compact solid state infrared lasers.

  • spectroscopic properties and concentration effects on luminescence behavior of nd3 doped zinc boro bismuthate glasses
    Materials Chemistry and Physics, 2013
    Co-Authors: Atul D Sontakke, K Annapurna
    Abstract:

    Abstract A detail investigation on laser spectroscopic properties as a function of Nd 3+ ions concentration in a new heavy metal oxide based Zinc–Boro–Bismuthate glasses is reported. The Judd–Ofelt analysis indicated an enhancement in Nd–O bond covalency as well as the local asymmetry of active ions on increase in dopant concentration from 0.1 to 1.5 mol%. Based on the Judd–Ofelt intensity parameters, several radiative properties such as transition probability, radiative lifetime, branching ratio and stimulated Emission Cross-section of Nd 3+ ions have been derived. The luminescence intensity has showed a strong increase up to 0.5 mol% Nd 2 O 3 , which then attains maximum at 1 mol% and falls down for further increase in dopant concentration. The luminescence quenching behavior at higher dopant concentration has been attributed to the hopping migration assisted energy transfer mechanism leading to the Cross-relaxation among active ions. The energy transfer micro-parameters for Cross-relaxation ( C DA ) and donor energy migration ( C DD ) have been derived from the luminescence decay analysis as well as spectral overlap function respectively. The high stimulated Emission Cross-section and smaller Cross-relaxation micro-parameters along with high quantum yield from the present glasses suggests their potential for compact infrared lasers and waveguide applications.