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1.
Emission properties of PbO–Bi2 O3 –Ga2 O3 glasses doped with Ho3+ were investigated for fiber-optic amplification at the 1.18 μm wavelength region. When the glasses were doped with Ho3+ ions only, there was a weak emission at 1.18 μm with a lifetime of ∼200 μs. However, when Yb3+ ions were codoped, the lifetime of the 1.18 μm emission increased to 630 μs together with a significant increase in intensity. A similar enhancement in the intensity and lifetimes was realized for the 2.05 μm emission. These effects are due to energy transfer from the Yb3+ :2 F5/2 to the Ho3+ :5 I6 level. Devitrification of the ternary PbO–Bi2 O3 –Ga2 O3 glasses was efficiently suppressed by adding 10 mol% GeO2 . Optimum Ho3+ concentration was ∼0.4 mol%, whereas Yb3+ ions can be added up to the solubility limit. 相似文献
2.
The previously studied system GeO2 -Bi2 O3 -TI2 O was extended with the addition of PbO using air- and water-quenched melted samples. Large areas of glass formation were found in the systems GeO2 –Bi2 O3 –PbO and GeO2 –PbO–Tl2 O at all but the lowest GeO2 contents. Glasses were examined by powder X-ray diffraction, differential thermal analysis, thermomechanical analysis, and Archimedes'technique to obtain glass transition and crystallization exotherm temperatures, thermal expansion coefficients, and densities, which are presented in diagrams for the GeO2 -PbO binary and for the two ternary systems. Based on calculated values of λ0 , the wavelength for zero material dispersion, compositions in this system may be useful for construction of ultralow-loss optical waveguides in the μm region. 相似文献
3.
Emission properties and energy transfer of PbO–Bi2 O3 –Ga2 O3 –GeO2 glasses codoped with Tm3+ and Tb3+ ions were investigated. The 1.48-μm emission due to the Tm3+ :3 H4 →3 F4 transition can be used to amplify the S-band (1460–1530-nm) signal light. With Tb3+ addition, the lifetime and emission intensity of the Tm3+ :3 F4 level decreased sharply via the Tm3+ :3 F4 →Tb3+ :7 F0,1,2 energy transfer. Population densities of the 3 F4 and 3 H4 levels in Tm3+ calculated from rate equations clearly verified that population inversion in Tm3+ ions became possible with as little as 0.1 mol% of Tb3+ addition. 相似文献
4.
Gangfeng Yang Qinyuan Zhang Dongmei Shi Zhonghong Jiang 《Journal of the American Ceramic Society》2007,90(1):307-310
We report the spectroscopic properties of Tm3+ -doped and Tm3+ /Ho3+ -codoped [Ga2 O3 –GeO2 –Bi2 O3 –PbO (PbF2 )] glasses for S-band optical amplifications. The Judd–Ofelt intensity parameters have been determined based on the measured absorption spectra. It is found that PbF2 -modified glasses exhibit a lower Ω2 value, and the addition of PbF2 caused the chemical bond associated with Tm3+ ions to be more ionic. The PbF2 -free glasses have large peak emission cross-sections in the range of 2.15–2.18 × 10−21 cm2 . Meanwhile, the studied glasses exhibit broad 1.47 μm emission with the full width at half-maximum of 119–126 nm. The results indicate that these glasses are useful host material for broadband S-band fiber amplifiers. 相似文献
5.
Interaction between Barium Titanate and Binary Glasses 总被引:2,自引:0,他引:2
Yoshirou Kuromitsu Sea Fue Wang Shoko Yoshikawa Robert E. Newriham 《Journal of the American Ceramic Society》1994,77(2):493-498
Interactions between BaTiO3 , and three binary glasses were studied through the reaction of BaTiO3 , powder with glass powder. For PbO–B2 O3 and PbO–SiO2 glasses, the reaction led to stable compound formation, the substitution of Pb in the BaTiO3 structure, and noticeable grain growth of BaTiO3 . The interaction phenomena for these two glass systems were very similar. The substitution of Pb into BaTiO3 is assisted by chemical reactions in which BaB2 O4 or Ba2 SiO4 is formed. The substitution into BaTiO3 also seems to be closely related to the grain growth of BaTiO3 . On the other hand, only compound formation was observed during the processing of BaTiO3 with Bi2 O3 –B2 O3 glass. Neither BaTiO3 grain growth nor Bi substitution took place with the Bi2 O3 –B2 O3 glass system. Based on the observed reactions and the glass viscosity, several sintering aids for BaTiO3 ceramic products are suggested in this paper. 相似文献
6.
Rongri Tan Qiang Wang Lianwen Wang Chenxi Li Kunquan Lu Shizheng Peng Lin Hu 《Journal of the American Ceramic Society》2007,90(9):2837-2842
The surface tension and density of x Bi2 O3 –(1− x )GeO2 (BGO) melts have been measured systematically from their respective melting points up to around 1480 K within 0.25≤ x ≤0.86. With the addition of Bi2 O3 , the density of this system increased smoothly with a positive curvature. Deviation of molar volume from ideality of this system melts decreased firstly, past a minimum at about x =0.4, and then increased. Partial molar volumes of Bi2 O3 and GeO2 have also been calculated based on the measured density data and compared with those of a binary bismuth borate system. On increasing the content of Bi2 O3 , the surface tension of BGO melts increased slowly when x <∼0.40, past a maximum at about x =0.50, and then decreased rapidly. In addition, the temperature coefficient of surface tension remained positive within the lower content range of Bi2 O3 , changed sign from positive to negative at about x =0.38, and then was almost independent of the composition within the measured temperature range when the Bi2 O3 content was increased further. 相似文献
7.
Marko Udovic Matjaz Valant Danilo Suvorov 《Journal of the American Ceramic Society》2004,87(4):591-597
Solid-state synthesis of compositions from the Bi2 O3 –TeO2 system show that, under an oxygen atmosphere, Te4+ oxidizes to Te6+ and yields four room-temperature stable compounds: Bi2 Te2 O8 , Bi2 TeO6 , Bi6 Te2 O15 , and new a compound with the nominal composition 7Bi2 O3 ·2TeO2 . Dense ceramics can be prepared from all these compounds by sintering between 650° and 800°C under an oxygen atmosphere. The permittivity of these compounds varies from ∼30 to ∼54, the Q × f value from 1.100 to 41.000 GHz (∼5 GHz), and the temperature coefficient of resonant frequency from −43 to −144 ppm/K. Bi6 Te2 O15 and 7Bi2 O3 ·2TeO2 do not react with silver, and, therefore, they have the potential to be used for applications in low-temperature cofired ceramic (LTCC) technology. 相似文献
8.
Takahiro Murata Masanori Torisaka Hiromichi Takebe Kenji Morinaga 《Journal of the American Ceramic Society》1998,81(8):2135-2139
Point defects were found in as-quenched GeO2 , 65CaO35Al2 O3 , and 65SrO35Ga2 O3 glasses on the basis of electron paramagnetic resonance (EPR) measurements. These defects were identified as Ge É centers in GeO2 glass and O- 2 , O- 3 , and M-OHC (oxygen hole center) (where M = Al, Ga) in 65CaO35Al2 O3 and 65SrO35Ga2 O3 glasses. The formation of Ge É centers in as-quenched GeO2 glass was due to the thermodynamic stability of GeO at the melting temperature. The latter oxygen-excess defects are supposed to be formed by excess oxygen ions derived from the modifiers in the aluminate and gallate glasses during the formation of these glasses. To investigate some of the properties of the oxygen-excess defects in the calcium aluminate and strontium gallate glasses, chromium ions were doped in these glasses as a probe and the relationship between the valency state of the chromium ion and the defects was determined. We conclude that the peroxy bonding (-O-O-) oxidizes the Cr3+ species to Cr4+ . Similar defects have been identified in host compounds that are used for Cr4+ tunable lasers. These results reveal that the point defects are necessary to stabilize the Cr4+ ions in glasses and crystals. 相似文献
9.
Anu Bajaj Atul Khanna Narendra K. Kulkarni Suresh K. Aggarwal 《Journal of the American Ceramic Society》2009,92(5):1036-1041
Bismuth borate glasses from the system: 40Bi2 O3 –59B2 O3 –1Tv2 O3 (where Tv=Al, Y, Nd, Sm, and Eu) and three glasses of composition: 40Bi2 O3 –60B2 O3 , 37.5Bi2 O3 –62.5B2 O3 and 38Bi2 O3 –60B2 O3 –2Al2 O3 were prepared by melt quenching and characterized by density, UV-visible absorption spectroscopy and differential thermal analysis (DTA) studies. Bismuth borate glasses exhibit a very strong optical absorption band just below their absorption edge. Glasses were devitrified by heat treatment at temperatures above their glass transition temperatures and the crystalline phases produced in them were characterized by Fourier transform infrared (FTIR) absorption spectroscopy and X-ray diffraction (XRD). Bi3 B5 O12 was found to be the most abundant phase in all devitrified samples. DTA studies on glasses and FTIR and XRD analysis on crystallized samples revealed that very small amounts of trivalent ion doping causes significant changes in the devitrification properties of bismuth borate glasses; rare-earth ions promote the formation of metastable BiBO3 –I and BiBO3 –II phases during glass crystallization. 相似文献
10.
Byung-Hae Jung Do-Kyung Lee Sang-Ho Sohn Hyung-Sun Kim 《Journal of the American Ceramic Society》2003,86(7):1202-1204
Because of their thermal, dielectric, and optical properties, new glass compositions and thick-filmed transparent dielectrics containing neodymium oxide (Nd2 O3 ) were studied as a source of purer images in plasma display panels. In the present study, PbO–B2 O3 –SiO2 and PbO–B2 O3 –SiO2 –ZnO–Al2 O3 were used as starting glass compositions, to which up to 25 wt% of Nd2 O3 then was added. Increased amounts of Nd2 O3 increased the glass transition temperature and dielectric constant of the bulk glasses and decreased the coefficient of thermal expansion. The fired thick films (around 30 μm) allowed selectively visible light to penetrate and showed deep absorption properties at 585 nm that were related to an extraneous gas from neon discharge. 相似文献
11.
Donald B. Dingwell 《Journal of the American Ceramic Society》1992,75(6):1656-1657
12.
Elena P. Kashchieva Yanko B. Dimitriev 《Journal of the American Ceramic Society》1997,80(6):1588-1590
Unusual droplet microaggregates are observed in TeO2 -rich glasses of the systems TeO2 –B2 O3 , TeO2 –GeO2 , TeO2 –B2 O3 –GeO2 , and TeO2 –GeO2 –V2 O5 . A decrease of the TeO2 content is established in the aggregates in comparison with the matrix. Their appearance is related to the process of metastable liquid-phase separation at high viscosity of the melts. 相似文献
13.
In the system Bi2 O3 -SiO2 -GeO2 , good glasses can be formed only from limited compositional regions consisting of 2 narrow strips along the lines x Bi2 O3 -(100-:t) GeO2 ( x ≤40) and 40Bi2 O3 y SiO2 (60- y )GeO2 (mol%); such glass is dark brown. Compositions from a large region (Bi2 O3 content <40 mol%) showed immiscibility. In the binary system Bi2 O3 -GeO2 , density and refractive index vary linearly with composition (mol%). Negative deviations of molar volume from ideality suggest that the coordination of a significant number of Ge ions is changing from 4-fold to 6-fold. Thermal expansion and electrical resistivity data are also reported. 相似文献
14.
Xian Feng Setsuhisa Tanabe Teiichi Hanada 《Journal of the American Ceramic Society》2001,84(1):165-171
The thermal stability and spectroscopic properties of Er2 O3 -doped TeO2 –GeO2 –ZnO–Na2 O–Y2 O3 glasses for 1.5 μm fiber amplifiers were investigated. The thermal stability of the 75TeO2 ·20ZnO· 5Na2 O glass was improved by introducing GeO2 and Y2 O3 . The radiative transition and the nonradiative transition have a dominant influence on the 4 I13/2 level lifetime of Er3+ in high- and low-GeO2 regions, respectively. Adding Y2 O3 increases the 4 I13/2 level lifetime of Er3+ significantly. The Judd–Ofelt (J-O) parameter Ω6 shows a strong correlation with the 1.5 μm emission bandwidth; and the larger the Ω6 , the wider the bandwidth. 相似文献
15.
Previous studies on glass formation involving GeO2 with Bi2 O3 , TI2 O, and PbO were extended by the use of Sb2 O3 . Wide areas of glass formation occur in the systems GeO2 -PbO-Sb2 O3 and GeO2 -Bi2 O3 -Sb2 O3 at all but the lowest GeO2 contents; the region of single-phase glasses in the system GeO2 -Tl2 O-Sb2 O3 is severely restricted. Glasses were examined by powder X-ray diffraction, differential thermal analysis, thermomechanical analysis, and Archimedes'technique to obtain glass transition and crystallization exotherm temperatures, thermal expansion coefficients, and densities; these properties are presented in diagrams for the GeO2 -Sb2 O3 binary and for two ternary systems. Based on calculated values of Δo ,the waveleneth for zero material dispersion. and dM/dΔ . the material disiersion slope at Δo , compositions in these systems may be useful for the construction of ultralow-loss optical waveguides in the 3 to 4 μm region. 相似文献
16.
Tsuyoshi Honma Yasuhiko Benino Takumi Fujiwara Takayuki Komatsu Ryuji Sato 《Journal of the American Ceramic Society》2005,88(4):989-992
The glass formation region, crystalline phases, second harmonic (SH) generation, and Nd:yttrium aluminum garnet (YAG) laser-induced crystallization in the Sm2 O3 –Bi2 O3 –B2 O3 system were clarified. The crystalline phases of Bi4 B2 O9 , Bi3 B5 O12 , BiBO3 , Sm x Bi1− x BO3 , and SmB3 O6 were formed through the usual crystallization in an electric furnace. The crystallized glasses consisting of BiBO3 and Sm x Bi1− x BO3 showed SH generations. The formation of the nonlinear optical BiB3 O6 phase was not confirmed. The formation (writing) region of crystal lines consisting of Sm x Bi1− x BO3 by YAG laser irradiation was determined, in which Sm2 O3 contents were∼10 mol%. The present study demonstrates that Sm2 O3 –Bi2 O3 –B2 O3 glasses are promising materials for optical functional applications. 相似文献
17.
Optical and material properties of (75− x )TeO2 – x GeO2 –20ZnO–5Na2 O–0.1Tm2 O3 glasses were investigated as candidate materials for an S-band Tm-doped fiber amplifier (TDFA). With increasing GeO2 content, the lifetime and the quantum efficiency of the 1.46 μm emission decreased slightly, while the emission bandwidth, the Vickers hardness, and thermal stability of the glass improved monotonically. Above 20 mol% GeO2 , the quantum efficiency decreased more rapidly with increasing GeO2 . We conclude that addition of a small amount of germania may improve material properties without deteriorating the optical properties of doped Tm3+ , and thus the germanotellurite fiber may be a more reliable material for the S-band TDFA in wavelength-division-multiplexing telecommunication. 相似文献
18.
Taigo Takaishi Masahide Takahashi Jisun Jin Takashi Uchino Toshinobu Yoko Masahide Takahashi 《Journal of the American Ceramic Society》2005,88(6):1591-1596
Structure of x PbO–(100− x )SiO2 ( x =25–89) glasses has been investigated by means of the X-ray and neutron diffraction and 29 Si MAS NMR measurements. In the radial distribution functions of all the glasses, the Pb–O correlation was observed at 0.23 nm, indicating that the PbO3 trigonal pyramids units do exist in the whole glass forming composition range. Furthermore the existence of the first Pb–Pb correlation at ∼0.385 nm in the whole composition range suggests that the basic structural unit is considered to be a Pb2 O4 unit, which consists of the edge-shared PbO3 trigonal pyramids. These results strongly imply that the Pb2 O4 units participate in the glass network constructed by SiO4 tetrahedra even at low PbO content. Differing from other lead-containing glass systems, these structural characteristics of Pb ions in the PbO–SiO2 glass system are responsible for the extremely wide glass-forming region. 相似文献
19.
E. F. RIEBLING P. E. BLASZYK D. W. SMITH 《Journal of the American Ceramic Society》1967,50(12):641-647
Density and viscosity results are presented for ternary Na2 O·GeO2 ·B2 O3 melts (∼600° to 1300°C) and glasses containing as much as 35 mole % Na2 O. Synthetic partial molar volume models indicate a fairly broad stability region for BO4 tetrahedra in the B2 O3 -rich melts. Similar models for GeO2 -rich melts reveal a more limited stability region for GeO6 octahedra. The expansion coefficient contours and viscosity isotherms confirm the volume-based conclusions for the liquid state. The high-temperature volume models were used to develop glass volume models that agree to within several percent of experiment. It has been concluded that the melts and glasses possess similar structures. The relatively greater compositional stability of GeO6 octahedra in the presence of B2 O3 (compared to Al2 O3 ) can be related to the smaller average number of oxygens around boron (III), at a fixed O/Ge ratio, compared to aluminum (III). Evidence is presented for a slight decrease of the thermal stability of GeO6 octahedra in the GeO2 -rich melts above about 1000°C. 相似文献
20.
Yong Beom Shin Hyung Tack Lim Yong Gyu Choi You Song Kim Jong Heo 《Journal of the American Ceramic Society》2000,83(4):787-791
Emission properties of 2.0 μm fluorescence and the energy transfer between Ho3+ and Tm3+ in 57PbO·25Bi2 O3 ·18Ga2 O3 (mol%) glass codoped with Ho3+ and Tm3+ were investigated. Cross-relaxation rates in Tm3+ increased approximately 5 times when the Tm2 O3 concentration was increased from 1.0 to 1.5 wt%. Coefficients of the forward Tm3+ → Ho3+ energy transfer were about 15 times larger than those of the Tm3+ ← Ho3+ backward transfer. Analysis of the energy transfer and gain spectra indicated that the highest gain at the 2.0 μm wavelength region could be achieved from the glass with 1.5 wt% of Tm2 O3 and 0.3 wt% of Ho2 O3 . 相似文献