RESUMO
We report on a new kind of white light emitting glass suitable for long-wavelength ultraviolet excitation by simultaneously emitting blue, green and red fluorescence, which is fabricated by melting of Ce(3+)-Tb(3+)-Mn(2+) co-doped borosilicate glass. The spectroscopic properties of singly, doubly and triply doped glasses have been reported and the energy transfer from Ce(3+) to Tb(3+) and Mn(2+) has also been investigated. By adjusting the concentration of different co-dopants, we obtained the ideal white light emitting borosilicate glass with the color coordinate (x = 0.318, y = 0.333).
Assuntos
Césio/análise , Vidro/química , Luminescência , Magnésio/análise , Análise Espectral/métodos , Térbio/análise , Raios UltravioletaRESUMO
The effect of Yb(3+) concentration on the broadband emission intensity and peak wavelength shift in Yb/Bi ions co-doped silicate glasses is investigated. The optimal Bi(2)O(3) concentration range is about 2.0-2.5 mol% in 65SiO(2)-10Al(2)O(3)-25CaO matrix (SAC glasses). For Yb/Bi codoped SAC glasses, the maximum emission intensity excited by 980 nm LD is ~30 times and 1.5 times higher than that of single Bi-doped SAC glasses excited by 980 nm and 808 nm LD, respectively, the peak emission shows obvious red-shift from 1185 nm to 1235 nm band with the Yb(2)O(3) concentration change from 0 to 3.0 mol%. For the same Yb(2)O(3) concentration in SAC glasses, the measured fluorescence lifetime near 1020 nm of single Yb(3+)-doped glasses is longer than that of Yb/Bi codoping glasses, which implyes the efficient energy transfer from Yb(3+) to Bi(n+) in SAC glasses. The results indicate Yb(2)O(3) can be induced into the bismuth-doped silicate glasses to enhance the emission intensity and control the peak wavelength.
RESUMO
We report on a new kind of green-emitting high silica luminous glass, which is fabricated by sintering of Ce(3+)-Tb(3+) co-doped porous glass. The spectra show that there are energy transfer between Ce(3+) and Tb(3+), and cross-relaxation between (5)D(3) and (5)D(4) energy level of Tb(3+). The energy transfer process can be adjusted by addition of Ca(2+) into the Ce(3+)-Tb(3+) co-doped porous glass, and the transfer rate can be enhanced about four times than that of Ce(3+)-Tb(3+) co-doped porous glass. The role of Ca(2+) has been discussed, and the fluorescence decay curve reveals that the Ca(2+) play an important role in energy transfer.
RESUMO
We present a systematic process of theoretical design and experimental fabrication of the large mode area and large negative dispersion photonic crystal fiber. An easily fabricated fiber structure is proposed. The influence of structure parameters deviations from the design on the chromatic dispersion are evaluated and a design rule is given. Finally our fabricated fiber and test results are demonstrated. The measured effective area of inner core mode is 40.7 mum(2) which is the largest effective area of high negative dispersion photonic crystal fibers that have been experimentally fabricated. The measured peak dispersion is -666.2ps/(nm.km) and the bandwidth is 40nm.