Borosilicate glass with high rare earth content was fabricated by traditional method. The influence of glass compositions and rare earth content on absorption spectra was examined and discussed. With increasing Sm2O3 ...Borosilicate glass with high rare earth content was fabricated by traditional method. The influence of glass compositions and rare earth content on absorption spectra was examined and discussed. With increasing Sm2O3 content, the intensity of characteristic absorption peak is increased and the absorption peak is broadened. With increasing of the ratios of SiO2/B2O3 and Al2O3/SiO2, the broadening degree of absorption peak is increased. The experimental results provide basis for making special optical glasses which have the characteristics of high absorption for special wavelength laser and high transparence for visible light.展开更多
Novel Er3+-doped bismuth lead strontiam glass was fabricated and characterized, and the absorption spectrum and upconversion spectrum of the glass were studied. The Judd-Ofelt intensity parameters Ωt (t=2, 4, 6) were...Novel Er3+-doped bismuth lead strontiam glass was fabricated and characterized, and the absorption spectrum and upconversion spectrum of the glass were studied. The Judd-Ofelt intensity parameters Ωt (t=2, 4, 6) were found to be Ω2=3.27×10-20 cm2, Ω4=1.15×10-20 cm2, and Ω6=0.38×10-20 cm2. The oscillator strength, the spontaneous transition probabilities, the fluorescence branching ratios, and excited state lifetimes were also measured and calculated. The upconversion emission intensity varies with the power of infrared excitation intensity. A plot of log Iup vs log IIR yields a straight line with slope 1.86, 1.88 and 1.85, corresponding to 525, 546, and 657 nm emission bands, respectively, which indicates that a two-photon process for the red and green emission.展开更多
Er^(3+)-doped heavy metal oxyfluoride silicate glass was fabricated and characterized, and the absorption spectrum and fluorescence spectrum of the glass were studied. The Judd-Ofelt intensity parameters Ω_t (t =2, ...Er^(3+)-doped heavy metal oxyfluoride silicate glass was fabricated and characterized, and the absorption spectrum and fluorescence spectrum of the glass were studied. The Judd-Ofelt intensity parameters Ω_t (t =2, 4, 6), spontaneous transition probability, fluorescence branching ratio and radiative lifetime of each energy levels for Er^(3+) were calculated by Judd-Ofelt theory, and stimulated emission cross-section of (()~4I_(13/2))→(()~4I_(15/2)) transition was calculated by McCumber theory. The results show that fluorescence full width at half maximum and stimulated emission cross-section of Er^(3+)-doped heavy metal oxyfluoride silicate glass are broad and large, respectively. Compared with other host glasses, the gain bandwidth property of Er^(3+)-doped heavy metal oxyfluoride silicate glass is close to those of tellurite and bismuth glasses, and has advantage over those of silicate, phosphate and germante glasses.展开更多
Dy^3＋-doped borate glasses （LBLB） with high effective visible fluorescence emission were synthesized. The absorption spectrum and fluorescence spectrum of this glass were measured and analyzed. By using J-O theory,...Dy^3＋-doped borate glasses （LBLB） with high effective visible fluorescence emission were synthesized. The absorption spectrum and fluorescence spectrum of this glass were measured and analyzed. By using J-O theory, the oscillator strengths for some absorption transitions were calculated according to the absorption spectra. The intensity parameters Ω1 （t = 2, 4, 6） of Dy^3＋ were determined by using a least-squares fitting approach, and the values are 4.04 × 10^-20, 1.30 × 10^-20 and 1.82 × 10^-20 cm, respectively. The root-mean-square deviation δrma was calculated. Under UV light excitation, Dy^3＋-doped borate glasses （LBLB） emit intense yellowish white lights. The excitation spectrum indicates that argon laser is the effective excitation source in Dy^3＋-doped LBLB glasses展开更多
Generally the preparation of lithium aluminosilicate（LAS） glasses is difficult on account of their high melting temperature. This research managed to prepare LAS glasses doped with Nd^3＋ ions by the conventional me...Generally the preparation of lithium aluminosilicate（LAS） glasses is difficult on account of their high melting temperature. This research managed to prepare LAS glasses doped with Nd^3＋ ions by the conventional melting and quenching technique, at a relatively low melting temperature and by the use of some additives. Lithium aluminosilicate glasses were transformed to glass-ceramics by controlled nucleation and the crystallization process. The characterizations were performed by differential thermal analysis, X-ray diffraction, UV-Vis-NIR scanning spectrophotometry, and fluorescence spectrometry. The research focused on the photoluminescence spectra of the initial glass and the glass-ceramics under different heat-treatment schedules. Three main fluorescence bands centering at about 890, 1065, and 1330 nm were ob- served, which corresponded to the transitions of ^4F3/2→^4I9/2, ^4F3/2→^4I11/2, and ^4F3/2→^4I13/2, respectively. Phase compositions of glass-ceramics were found to affect their fluorescent characteristics considerably. The fluorescent intensity increased markedly when Nd^3 ＋ ions entered the LixAlxSi1-xO2 β-eucryptite solid solution （SS）. Quenching occurred when Nd^3 ＋ ions located at LixAlxSi3-xO6β-eucryptite SS. Quenching disappeared after LixAlxSi3-xO6 β-eucryptite SS recrystallized into β-spodumene SS. The effectively induced cross section σin of Nd^3＋ ions located at the LixAlxSi1-xO2 β-eucryptite SS was 1.931 ×10^-21 cm^2 at 1065 nm.展开更多
Cordierite-based glass-ceramics with non-stoichiometric composition doped with rare earth oxide (REO_2) and heavy metal oxide (M_2O_3) respectively were fabricated from glass powders. After sintering and crystallizati...Cordierite-based glass-ceramics with non-stoichiometric composition doped with rare earth oxide (REO_2) and heavy metal oxide (M_2O_3) respectively were fabricated from glass powders. After sintering and crystallization heat treatment, various physical properties, including compact density and apparent porosity, were examined to evaluate the sintering behavior of cordierite-based glass-ceramics. Results show that the additives both heavy metal oxide and rare earth oxide promote the sintering and lower the phase temperature from μ- to α-cordierite as well as affect the dielectric properties of sintered glass-ceramics. The complete-densification temperature for samples is as low as 900 ℃. The materials have a low dielectric constant (≈5), a low thermal expansion coefficient ((2.80～3.52)×10^(-6) ℃^(-1)) and a low dissipation factor (≤0.2%) and can be co-fired with high conductivity metals such as Au, Cu, Ag/Pd paste at low temperature (below 950 ℃), which makes it to be a promising material for low-temperature co-fired ceramic substrates.展开更多
CaO-SiO2-B2O3 ：Sm2O3 glasses were synthesized in air atmosphere with conventional high temperature process. The optimal temperature of synthesis, the absorption spectrum and the luminescent properties of the glasses ...CaO-SiO2-B2O3 ：Sm2O3 glasses were synthesized in air atmosphere with conventional high temperature process. The optimal temperature of synthesis, the absorption spectrum and the luminescent properties of the glasses were studied. The fluorescence spectrum of Sm^3＋ was observed in CaO-SiO2-B2O3 ： Sm2O3 glasses. The fluorescence spectrum of the sample has three major emission bands peaking at 568, 605 and 650 nm respectively. The strongest emission band peak at 605 nm. It is concluded that the emissions were caused by the f-f transition of the 4f electrons of Sm^3＋. The emission bands peaking at 568, 604 and 650 nm correspond to the ^4G5/2→^6H5/2 transition, ^4G5/2→^6H7/2 transition and ^4G5/2→^6H9/2 trasition respectively. The luminescent properties of CaO-SiO2-B2O3 glasses indicate that the glass can convert the ultraviolet in the sunlight into red light, thus increasing the intensity of red light. The luminescent properties of these glasses may be used to make kinds of light-conversion glass for agriculture.展开更多
文摘Borosilicate glass with high rare earth content was fabricated by traditional method. The influence of glass compositions and rare earth content on absorption spectra was examined and discussed. With increasing Sm2O3 content, the intensity of characteristic absorption peak is increased and the absorption peak is broadened. With increasing of the ratios of SiO2/B2O3 and Al2O3/SiO2, the broadening degree of absorption peak is increased. The experimental results provide basis for making special optical glasses which have the characteristics of high absorption for special wavelength laser and high transparence for visible light.
文摘Novel Er3+-doped bismuth lead strontiam glass was fabricated and characterized, and the absorption spectrum and upconversion spectrum of the glass were studied. The Judd-Ofelt intensity parameters Ωt (t=2, 4, 6) were found to be Ω2=3.27×10-20 cm2, Ω4=1.15×10-20 cm2, and Ω6=0.38×10-20 cm2. The oscillator strength, the spontaneous transition probabilities, the fluorescence branching ratios, and excited state lifetimes were also measured and calculated. The upconversion emission intensity varies with the power of infrared excitation intensity. A plot of log Iup vs log IIR yields a straight line with slope 1.86, 1.88 and 1.85, corresponding to 525, 546, and 657 nm emission bands, respectively, which indicates that a two-photon process for the red and green emission.
文摘Er^(3+)-doped heavy metal oxyfluoride silicate glass was fabricated and characterized, and the absorption spectrum and fluorescence spectrum of the glass were studied. The Judd-Ofelt intensity parameters Ω_t (t =2, 4, 6), spontaneous transition probability, fluorescence branching ratio and radiative lifetime of each energy levels for Er^(3+) were calculated by Judd-Ofelt theory, and stimulated emission cross-section of (()~4I_(13/2))→(()~4I_(15/2)) transition was calculated by McCumber theory. The results show that fluorescence full width at half maximum and stimulated emission cross-section of Er^(3+)-doped heavy metal oxyfluoride silicate glass are broad and large, respectively. Compared with other host glasses, the gain bandwidth property of Er^(3+)-doped heavy metal oxyfluoride silicate glass is close to those of tellurite and bismuth glasses, and has advantage over those of silicate, phosphate and germante glasses.
文摘Dy^3＋-doped borate glasses （LBLB） with high effective visible fluorescence emission were synthesized. The absorption spectrum and fluorescence spectrum of this glass were measured and analyzed. By using J-O theory, the oscillator strengths for some absorption transitions were calculated according to the absorption spectra. The intensity parameters Ω1 （t = 2, 4, 6） of Dy^3＋ were determined by using a least-squares fitting approach, and the values are 4.04 × 10^-20, 1.30 × 10^-20 and 1.82 × 10^-20 cm, respectively. The root-mean-square deviation δrma was calculated. Under UV light excitation, Dy^3＋-doped borate glasses （LBLB） emit intense yellowish white lights. The excitation spectrum indicates that argon laser is the effective excitation source in Dy^3＋-doped LBLB glasses
基金Project supported bythe Chinese Ministry of Educationfor Financial Support (KB20026) and the Chinese Ministry of Educa-tion for Financial Support (205037)
文摘Generally the preparation of lithium aluminosilicate（LAS） glasses is difficult on account of their high melting temperature. This research managed to prepare LAS glasses doped with Nd^3＋ ions by the conventional melting and quenching technique, at a relatively low melting temperature and by the use of some additives. Lithium aluminosilicate glasses were transformed to glass-ceramics by controlled nucleation and the crystallization process. The characterizations were performed by differential thermal analysis, X-ray diffraction, UV-Vis-NIR scanning spectrophotometry, and fluorescence spectrometry. The research focused on the photoluminescence spectra of the initial glass and the glass-ceramics under different heat-treatment schedules. Three main fluorescence bands centering at about 890, 1065, and 1330 nm were ob- served, which corresponded to the transitions of ^4F3/2→^4I9/2, ^4F3/2→^4I11/2, and ^4F3/2→^4I13/2, respectively. Phase compositions of glass-ceramics were found to affect their fluorescent characteristics considerably. The fluorescent intensity increased markedly when Nd^3 ＋ ions entered the LixAlxSi1-xO2 β-eucryptite solid solution （SS）. Quenching occurred when Nd^3 ＋ ions located at LixAlxSi3-xO6β-eucryptite SS. Quenching disappeared after LixAlxSi3-xO6 β-eucryptite SS recrystallized into β-spodumene SS. The effectively induced cross section σin of Nd^3＋ ions located at the LixAlxSi1-xO2 β-eucryptite SS was 1.931 ×10^-21 cm^2 at 1065 nm.
文摘Cordierite-based glass-ceramics with non-stoichiometric composition doped with rare earth oxide (REO_2) and heavy metal oxide (M_2O_3) respectively were fabricated from glass powders. After sintering and crystallization heat treatment, various physical properties, including compact density and apparent porosity, were examined to evaluate the sintering behavior of cordierite-based glass-ceramics. Results show that the additives both heavy metal oxide and rare earth oxide promote the sintering and lower the phase temperature from μ- to α-cordierite as well as affect the dielectric properties of sintered glass-ceramics. The complete-densification temperature for samples is as low as 900 ℃. The materials have a low dielectric constant (≈5), a low thermal expansion coefficient ((2.80～3.52)×10^(-6) ℃^(-1)) and a low dissipation factor (≤0.2%) and can be co-fired with high conductivity metals such as Au, Cu, Ag/Pd paste at low temperature (below 950 ℃), which makes it to be a promising material for low-temperature co-fired ceramic substrates.
文摘CaO-SiO2-B2O3 ：Sm2O3 glasses were synthesized in air atmosphere with conventional high temperature process. The optimal temperature of synthesis, the absorption spectrum and the luminescent properties of the glasses were studied. The fluorescence spectrum of Sm^3＋ was observed in CaO-SiO2-B2O3 ： Sm2O3 glasses. The fluorescence spectrum of the sample has three major emission bands peaking at 568, 605 and 650 nm respectively. The strongest emission band peak at 605 nm. It is concluded that the emissions were caused by the f-f transition of the 4f electrons of Sm^3＋. The emission bands peaking at 568, 604 and 650 nm correspond to the ^4G5/2→^6H5/2 transition, ^4G5/2→^6H7/2 transition and ^4G5/2→^6H9/2 trasition respectively. The luminescent properties of CaO-SiO2-B2O3 glasses indicate that the glass can convert the ultraviolet in the sunlight into red light, thus increasing the intensity of red light. The luminescent properties of these glasses may be used to make kinds of light-conversion glass for agriculture.
