The Eu3＋-doped La2Zr207 phosphor with rod-like morphology was successfully synthesized by conventional solid state reaction and hydrothermal method. X-ray diffraction patterns, transmission electron microscopy, and p...The Eu3＋-doped La2Zr207 phosphor with rod-like morphology was successfully synthesized by conventional solid state reaction and hydrothermal method. X-ray diffraction patterns, transmission electron microscopy, and photoluminescence spectra were employed to charac- terize its structure and morphology as well as luminescent properties. The results indicated that the red-emitting phosphor La2Zr207：Eu3＋ had well crystallized and belonged to the cubic structure with space group of Fd3m. The as-obtained product mainly appeared as straight nanorods with an average diameter of 47 nm and length of 50-700 nm. The pos- sible growth mechanism was also discussed. It was found that under blue excitation with a wavelength of 466 nm, the La2Zr2OT：Eu3＋ phosphor exhibited a characteristic red emission at 616 nm that was attributed to the hypersensitive 5D0--＊TF2 electric dipole transition of Eu3＋ ions. Meanwhile, it was more interesting to note that the emission of 5D1--＊TFj （J=0, 1, 2） transitions and the splitting patterns of 5D0---＋TFJ （J--l, 2, 4） transitions of Eu3＋ ions can be observed in the luminescent spectra of La2Zr207：Eu3＋. It was demonstrated that Eu3＋ preferred to occupy a low symmetry site.展开更多
In this study Cu<sup>2+</sup>+Eu<sup>3+</sup> co-doped ZnO(ZnO/Cu<sup>2+</sup>+Eu<sup>3+</sup>) solid solution powders were synthesized by solution combustion method usi...In this study Cu<sup>2+</sup>+Eu<sup>3+</sup> co-doped ZnO(ZnO/Cu<sup>2+</sup>+Eu<sup>3+</sup>) solid solution powders were synthesized by solution combustion method using as oxidant agent zinc nitrate hexahydrate and as fuel urea;the Cu<sup>2+</sup> concentrations were 0, 1, 2, 3, 10, and 20 %Wt;the Eu<sup>3+</sup> ion concentration was fixed in 3%Wt. The samples after were annealed at 900°C by 20 h in air. The structural results showed the largely presence of a wurtzite solid solution of Cu<sup>2+</sup>+Eu<sup>3+</sup>doped ZnO, at high Cu<sup>2+</sup> doping CuO and Eu<sub>2</sub>CuO<sub>4</sub> phases are also present. Morphological properties were analyzed using scanning electron microscopy (SEM) technique. However it is important to remark that the Cu<sup>2+</sup> ions suppress the Eu<sup>3+</sup> ion photoluminescence (PL) by means of an overlap mechanism between Cu<sup>2+</sup> absorption band and Eu<sup>3+</sup>emission band (e.g. <sup>5</sup>D<sub>0</sub>→<sup>7</sup>F<sub>2</sub>) of the Eu<sup>3+</sup> emission spectra.展开更多
According to density matrix equations of the interaction between light and matter, the expression for the suscep- tibility of the Eu^3＋ ：Y2SiO5 crystal is obtained. When the control field is a Gaussian beam, we inve...According to density matrix equations of the interaction between light and matter, the expression for the suscep- tibility of the Eu^3＋ ：Y2SiO5 crystal is obtained. When the control field is a Gaussian beam, we investigate and analyze the influence of probe detuning, the Rabi frequency of the control field and the laser line width on the transverse optical properties. We also analyze the influence of the dope-ion concentration on electromagnetieally induced transparency （EIT）. The analysis result indicates that the transmission is not a monotonic function of the dope-ion concentration. Based on the influences of various parameters on the transverse optical properties, we choose the appropriate parameters to realize the desired EIT and gradient refractive index, which has applications in focusing and imaging.展开更多
文摘The Eu3＋-doped La2Zr207 phosphor with rod-like morphology was successfully synthesized by conventional solid state reaction and hydrothermal method. X-ray diffraction patterns, transmission electron microscopy, and photoluminescence spectra were employed to charac- terize its structure and morphology as well as luminescent properties. The results indicated that the red-emitting phosphor La2Zr207：Eu3＋ had well crystallized and belonged to the cubic structure with space group of Fd3m. The as-obtained product mainly appeared as straight nanorods with an average diameter of 47 nm and length of 50-700 nm. The pos- sible growth mechanism was also discussed. It was found that under blue excitation with a wavelength of 466 nm, the La2Zr2OT：Eu3＋ phosphor exhibited a characteristic red emission at 616 nm that was attributed to the hypersensitive 5D0--＊TF2 electric dipole transition of Eu3＋ ions. Meanwhile, it was more interesting to note that the emission of 5D1--＊TFj （J=0, 1, 2） transitions and the splitting patterns of 5D0---＋TFJ （J--l, 2, 4） transitions of Eu3＋ ions can be observed in the luminescent spectra of La2Zr207：Eu3＋. It was demonstrated that Eu3＋ preferred to occupy a low symmetry site.
文摘In this study Cu<sup>2+</sup>+Eu<sup>3+</sup> co-doped ZnO(ZnO/Cu<sup>2+</sup>+Eu<sup>3+</sup>) solid solution powders were synthesized by solution combustion method using as oxidant agent zinc nitrate hexahydrate and as fuel urea;the Cu<sup>2+</sup> concentrations were 0, 1, 2, 3, 10, and 20 %Wt;the Eu<sup>3+</sup> ion concentration was fixed in 3%Wt. The samples after were annealed at 900°C by 20 h in air. The structural results showed the largely presence of a wurtzite solid solution of Cu<sup>2+</sup>+Eu<sup>3+</sup>doped ZnO, at high Cu<sup>2+</sup> doping CuO and Eu<sub>2</sub>CuO<sub>4</sub> phases are also present. Morphological properties were analyzed using scanning electron microscopy (SEM) technique. However it is important to remark that the Cu<sup>2+</sup> ions suppress the Eu<sup>3+</sup> ion photoluminescence (PL) by means of an overlap mechanism between Cu<sup>2+</sup> absorption band and Eu<sup>3+</sup>emission band (e.g. <sup>5</sup>D<sub>0</sub>→<sup>7</sup>F<sub>2</sub>) of the Eu<sup>3+</sup> emission spectra.
基金Supported by the National Natural Science Foundation of China under Grant Nos 11104185,11174084,10934011 and 61378060the National Basic Research Program of China under Grant No 2012CB921904+2 种基金the Innovation Program of Shanghai Municipal Education Commission under Grant No 11YZ118the Shanghai Dawn Project of Shanghai Education Commission under Grant No11SG44the Hujiang Foundation of China under Grant No B14004
文摘According to density matrix equations of the interaction between light and matter, the expression for the suscep- tibility of the Eu^3＋ ：Y2SiO5 crystal is obtained. When the control field is a Gaussian beam, we investigate and analyze the influence of probe detuning, the Rabi frequency of the control field and the laser line width on the transverse optical properties. We also analyze the influence of the dope-ion concentration on electromagnetieally induced transparency （EIT）. The analysis result indicates that the transmission is not a monotonic function of the dope-ion concentration. Based on the influences of various parameters on the transverse optical properties, we choose the appropriate parameters to realize the desired EIT and gradient refractive index, which has applications in focusing and imaging.
