Eu3+doped CaMoO4 phosphors were synthesized by using the solid state reaction method.The x−ray diffraction shows that all the patterns of the obtained samples are indexed to the sheelite structure.Red afterglow origin...Eu3+doped CaMoO4 phosphors were synthesized by using the solid state reaction method.The x−ray diffraction shows that all the patterns of the obtained samples are indexed to the sheelite structure.Red afterglow originating from the 5D0–7FJ(J=0,1,2,3,4)transitions of Eu^(3+) was observed after the samples were excited by 254 nm and the optimal Eu3+concentration in the CaMoO_(4) matrix was experimentally determined to be 0.50%.A possible explanation of this afterglow property is also discussed.展开更多
Stable mode-locking in a diode-pumped Yb:YAG laser was obtained with a very fast semiconductor sat-urable absorber mirror (SESAM). The pulse width was measured to be 4 ps at the central wavelength of 1047 nm. The aver...Stable mode-locking in a diode-pumped Yb:YAG laser was obtained with a very fast semiconductor sat-urable absorber mirror (SESAM). The pulse width was measured to be 4 ps at the central wavelength of 1047 nm. The average power was 200 mW and the repetition rate was 200 MHz.展开更多
Eu3＋ and Ho3＋ doped Sr2TiO4 were synthesized by using solid-state reactions. Samples sintered at 1300 ℃ for 6 h could be indexed to Sr2TiO4 with a single phase. Eu3＋ in Sr2TiO4 emitted orange light under the excit...Eu3＋ and Ho3＋ doped Sr2TiO4 were synthesized by using solid-state reactions. Samples sintered at 1300 ℃ for 6 h could be indexed to Sr2TiO4 with a single phase. Eu3＋ in Sr2TiO4 emitted orange light under the excitation at 365 nm in a broad band which was coupled well with the strongest emission of high pressure mercury vapor lamps. Ho3＋ in Sr2TiO4 emitted yellow light under blue excitation from 450 to 460 nm which agreed well with the emission of blue InGaN-based light-emitting diodes. The present results indicated that Sr2TiO4 was a promis- ing host for high pressure mercury vapor lamps or white light-emitting diodes.展开更多
A series of Eu3＋-Bi3＋ co-doped CaMoO4 red phosphors were synthesized via the solid-sate reaction method. The crystal structures of the obtained samples were identified by X-ray powder diffraction （XRD）. The photol...A series of Eu3＋-Bi3＋ co-doped CaMoO4 red phosphors were synthesized via the solid-sate reaction method. The crystal structures of the obtained samples were identified by X-ray powder diffraction （XRD）. The photoluminescence property was investigated, and the results showed that the intensity of excitation spectra and emission spectra could be changed with different doping ratios of Bi3＋/Eu3＋. The proposed explanation of these changes was from the energy transfer between Bi3＋ and Eu3＋ and the unbalanced charge from the substitution of Eu3＋ and Bi3＋ for Ca2＋ in CaMoO4. The obtained samples are a promising red light emitting phosphor for the needs of different excitation sources with near-UV and blue GaN-based chips.展开更多
基金Supported by the National Natural Science Foundation of China under Grant No.21071034.
文摘Eu3+doped CaMoO4 phosphors were synthesized by using the solid state reaction method.The x−ray diffraction shows that all the patterns of the obtained samples are indexed to the sheelite structure.Red afterglow originating from the 5D0–7FJ(J=0,1,2,3,4)transitions of Eu^(3+) was observed after the samples were excited by 254 nm and the optimal Eu3+concentration in the CaMoO_(4) matrix was experimentally determined to be 0.50%.A possible explanation of this afterglow property is also discussed.
基金This work was supported by the National Key Basic Research Special Foundation of China (No. G1999075201-2) the National Natural Science Foundation of China (No. 69978016, 60178008) the Foundation of the Optoelectronic United Center of Tianjin, the Na
文摘Stable mode-locking in a diode-pumped Yb:YAG laser was obtained with a very fast semiconductor sat-urable absorber mirror (SESAM). The pulse width was measured to be 4 ps at the central wavelength of 1047 nm. The average power was 200 mW and the repetition rate was 200 MHz.
基金Project supported by National Natural Science Foundation of China (21071034)
文摘Eu3＋ and Ho3＋ doped Sr2TiO4 were synthesized by using solid-state reactions. Samples sintered at 1300 ℃ for 6 h could be indexed to Sr2TiO4 with a single phase. Eu3＋ in Sr2TiO4 emitted orange light under the excitation at 365 nm in a broad band which was coupled well with the strongest emission of high pressure mercury vapor lamps. Ho3＋ in Sr2TiO4 emitted yellow light under blue excitation from 450 to 460 nm which agreed well with the emission of blue InGaN-based light-emitting diodes. The present results indicated that Sr2TiO4 was a promis- ing host for high pressure mercury vapor lamps or white light-emitting diodes.
基金Project supported by the National Natural Science Foundation of China (21071034)
文摘A series of Eu3＋-Bi3＋ co-doped CaMoO4 red phosphors were synthesized via the solid-sate reaction method. The crystal structures of the obtained samples were identified by X-ray powder diffraction （XRD）. The photoluminescence property was investigated, and the results showed that the intensity of excitation spectra and emission spectra could be changed with different doping ratios of Bi3＋/Eu3＋. The proposed explanation of these changes was from the energy transfer between Bi3＋ and Eu3＋ and the unbalanced charge from the substitution of Eu3＋ and Bi3＋ for Ca2＋ in CaMoO4. The obtained samples are a promising red light emitting phosphor for the needs of different excitation sources with near-UV and blue GaN-based chips.
