In C3v point group symmetry, crystal field energy levels of Yb3+ in LiNbO3 were assigned on the basis of DSCPCF model and PCF model. As compared with the experimental values of crystal field energy levels, the root me...In C3v point group symmetry, crystal field energy levels of Yb3+ in LiNbO3 were assigned on the basis of DSCPCF model and PCF model. As compared with the experimental values of crystal field energy levels, the root mean square standard deviation is 16.09cm-1 for the calculation of the DSCPCF model and is 30.30cm-1 for the PCF, respectively. This result shows that the DSCPCF model can fit the experimental values of crystal field energy levels better than the PCF model. At the same time, Absorption spectra and Emission spectra of Yb3+ in LiNbO3 were analyzed and the peaks that appear in Figures were also assigned reasonably.展开更多
In the present paper, linear sweep polarography (LPS) was employed to study Yb 3+ KMnO 4 system. Results show that this system is characterized as a catalytic wave. The first step of Yb 3+ reduction was th...In the present paper, linear sweep polarography (LPS) was employed to study Yb 3+ KMnO 4 system. Results show that this system is characterized as a catalytic wave. The first step of Yb 3+ reduction was the one electron reduction to Yb 2+ , and improvement in the sensitivity of Yb 3+ was studied. Convolution voltammetry and cyclic voltammetry were employed to determine the rate constant and to confirm the process of electrode. The effects of various parameters, including pH, electrolyte, catalyst concentration and surface active substance on the reduction process were examined.展开更多
采用离子交换法制备铒镱共掺磷酸盐波导光放大器,实验研究交换熔盐中的Ag离子浓度和交换时间对波导折射率和深度的影响.首先通过微电子的一些基本工艺制备8μm,10μm以及12μm宽度的Al条形掩模,并根据不同的AgNO_3浓度以及不同的交换时...采用离子交换法制备铒镱共掺磷酸盐波导光放大器,实验研究交换熔盐中的Ag离子浓度和交换时间对波导折射率和深度的影响.首先通过微电子的一些基本工艺制备8μm,10μm以及12μm宽度的Al条形掩模,并根据不同的AgNO_3浓度以及不同的交换时间得到不同的波导深度样品.然后在光学位移平台上对制备的条形波导进行测试,其中10μm宽,6μm深的条形波导的信号光输出功率为9μW,信号光净增益达3.0 d B/cm.展开更多
The trivalent ytterbium(Yb^(3+))ion has been extensively used as an emitter in short-wave infrared(SWIR)lasers,a sensitizer to activate other lanthanide ions for up-conversion luminescence,and a spectral converter in ...The trivalent ytterbium(Yb^(3+))ion has been extensively used as an emitter in short-wave infrared(SWIR)lasers,a sensitizer to activate other lanthanide ions for up-conversion luminescence,and a spectral converter in Ln^(3+)-Yb^(3+)doubly doped quantum cutting phosphors.Here we report a new function of the Yb^(3+)ion—as an efficient emitting center for SWIR persistent luminescence.We have developed the first real SWIR persistent phosphor,MgGeO3:Yb^(3+),which exhibits very-long persistent luminescence at around 1000 nm for longer than 100 h.The MgGeO3:Yb^(3+)phosphor is spectrally transparent to visible/near-infrared light(~400–900 nm)and is a promising ultraviolet-to-SWIR spectral convertor.The MgGeO3:Yb^(3+)phosphor also exhibits a photostimulated persistent luminescence capability,where the SWIR persistent emission in an ultraviolet-light pre-irradiated sample can be rejuvenated by low-energy light(white or red light)stimulation.The MgGeO3:Yb^(3+)phosphor is expected to have promising applications in biomedical imaging,night-vision surveillance and photovoltaics.展开更多
This study addressed the effects of Yb3+ on voltage-gated sodium currents in rat hippocampal neurons using the whole-cell patch-clamp technique. Voltage-clamp recordings in single neurons were filtered and stored in a...This study addressed the effects of Yb3+ on voltage-gated sodium currents in rat hippocampal neurons using the whole-cell patch-clamp technique. Voltage-clamp recordings in single neurons were filtered and stored in a computer. Yb3+ increased the amplitude of sodium currents in a concentration-dependent and voltage-dependent manner. The 50 % enhancement concentration of Yb3+ on sodium currents was about 8.97 lmol/L, which was different from the inhibitory effects of Yb3+ on potassium current. The analysis on the activation and inactivation kinetics of Na+ current showed that 100 lmol/L Yb3+ did not change the process of activation and inactivation. In addition, the times reaching the peak of current(t) and inactivated time constant(s) were voltage dependent. 100 lmol/L Yb3+ significantly prolonged the time to peak at-70 and-80 mV. The effect disappeared at the positive direction of-70 mV. Furthermore, Yb3+ decreased s values to more positive values than-80 mV. In total, Yb3+ did not change the process of activation, but impelled inactivated process. Yb3+ mainly increased the Na+ current through changing its conductance. It might be one of the mechanisms that Yb3+ affected the hippocampal neurons.展开更多
We reported a passive Q-switched diode laser pumped Yb: YAG microchip laser with an ion-implanted semi-insulating GaAs wafer. The wafer was implanted with 400-keV As+ in the concentration of 1016 ions/cm2. To decrease...We reported a passive Q-switched diode laser pumped Yb: YAG microchip laser with an ion-implanted semi-insulating GaAs wafer. The wafer was implanted with 400-keV As+ in the concentration of 1016 ions/cm2. To decrease the non-saturable loss, we annealed the ion-implanted GaAs at 500℃ for 5 minutes and coated both sides of the ion-implanted GaAs with antireflection (AR) and high reflection (HR) films, respectively. Using GaAs wafer as an absorber and an output coupler, we obtained 52-ns pulse duration of single pulse.展开更多
The use of red light or near-infrared radiation as a luminescent probe for in vivo bio imaging is crucial in order to restrict the strong absorption of short-wavelength light below 600 nm in tissue. It is demonstrated...The use of red light or near-infrared radiation as a luminescent probe for in vivo bio imaging is crucial in order to restrict the strong absorption of short-wavelength light below 600 nm in tissue. It is demonstrated that the emission color of Yb/Ho codoped NaYFa nanoparticles can be tuned from green to red by incorporating Ce3＋ ions. However, compared with that of the NaYF4：Yb/Ho nanoparticles, the photoluminescence intensity of the Ce3＋-tridoped NaYF4：Yb/Ho nanoparticles is drastically reduced. In this work, Ce3＋-incorporated core/shell NaYF4： Yb3＋50%@NaYF4：Ho3＋0.5% nanoparticles are prepared. A strong red emission and a high-intensity ratio between the red emission and green emission are obtained in these upconversion nanoparticles. The emission intensity in- creases by a factor higher than 120 when compared with that of the NaYF4 ：Yb/Ho/Ce nanoparticles. This result indicates that the Ce3＋ incorporation into the NaYF4：Yb/Ho nanoparticles promotes a strong quenching effect and reduces the emission intensity; however, the quenching effect can be significantly reduced by incorporating the Ce3＋ ions into the core/shell NaYF4：yb3＋50%@NaYF4：Ho3＋0.5% nanoparticles. A theoretical model is proposed to explain the presence of the quenching effect in the NaYF4：Yb/Ho/Ce nanoparticles, demonstrating that the quenching is mainly related to the interaction between the Yb3＋ and Ce3＋ ions.展开更多
文摘In C3v point group symmetry, crystal field energy levels of Yb3+ in LiNbO3 were assigned on the basis of DSCPCF model and PCF model. As compared with the experimental values of crystal field energy levels, the root mean square standard deviation is 16.09cm-1 for the calculation of the DSCPCF model and is 30.30cm-1 for the PCF, respectively. This result shows that the DSCPCF model can fit the experimental values of crystal field energy levels better than the PCF model. At the same time, Absorption spectra and Emission spectra of Yb3+ in LiNbO3 were analyzed and the peaks that appear in Figures were also assigned reasonably.
文摘In the present paper, linear sweep polarography (LPS) was employed to study Yb 3+ KMnO 4 system. Results show that this system is characterized as a catalytic wave. The first step of Yb 3+ reduction was the one electron reduction to Yb 2+ , and improvement in the sensitivity of Yb 3+ was studied. Convolution voltammetry and cyclic voltammetry were employed to determine the rate constant and to confirm the process of electrode. The effects of various parameters, including pH, electrolyte, catalyst concentration and surface active substance on the reduction process were examined.
文摘采用离子交换法制备铒镱共掺磷酸盐波导光放大器,实验研究交换熔盐中的Ag离子浓度和交换时间对波导折射率和深度的影响.首先通过微电子的一些基本工艺制备8μm,10μm以及12μm宽度的Al条形掩模,并根据不同的AgNO_3浓度以及不同的交换时间得到不同的波导深度样品.然后在光学位移平台上对制备的条形波导进行测试,其中10μm宽,6μm深的条形波导的信号光输出功率为9μW,信号光净增益达3.0 d B/cm.
基金support from the National Science Foundation(CAREER DMR-0955908,DMR-1403929)support from the National Natural Science Foundation of China(no.81171463)support from the China Scholarship Council.
文摘The trivalent ytterbium(Yb^(3+))ion has been extensively used as an emitter in short-wave infrared(SWIR)lasers,a sensitizer to activate other lanthanide ions for up-conversion luminescence,and a spectral converter in Ln^(3+)-Yb^(3+)doubly doped quantum cutting phosphors.Here we report a new function of the Yb^(3+)ion—as an efficient emitting center for SWIR persistent luminescence.We have developed the first real SWIR persistent phosphor,MgGeO3:Yb^(3+),which exhibits very-long persistent luminescence at around 1000 nm for longer than 100 h.The MgGeO3:Yb^(3+)phosphor is spectrally transparent to visible/near-infrared light(~400–900 nm)and is a promising ultraviolet-to-SWIR spectral convertor.The MgGeO3:Yb^(3+)phosphor also exhibits a photostimulated persistent luminescence capability,where the SWIR persistent emission in an ultraviolet-light pre-irradiated sample can be rejuvenated by low-energy light(white or red light)stimulation.The MgGeO3:Yb^(3+)phosphor is expected to have promising applications in biomedical imaging,night-vision surveillance and photovoltaics.
基金supported by the National Natural Science Foundation of China(21177078)the Natural Science Foundation of Shanxi Province(2012011036-5)
文摘This study addressed the effects of Yb3+ on voltage-gated sodium currents in rat hippocampal neurons using the whole-cell patch-clamp technique. Voltage-clamp recordings in single neurons were filtered and stored in a computer. Yb3+ increased the amplitude of sodium currents in a concentration-dependent and voltage-dependent manner. The 50 % enhancement concentration of Yb3+ on sodium currents was about 8.97 lmol/L, which was different from the inhibitory effects of Yb3+ on potassium current. The analysis on the activation and inactivation kinetics of Na+ current showed that 100 lmol/L Yb3+ did not change the process of activation and inactivation. In addition, the times reaching the peak of current(t) and inactivated time constant(s) were voltage dependent. 100 lmol/L Yb3+ significantly prolonged the time to peak at-70 and-80 mV. The effect disappeared at the positive direction of-70 mV. Furthermore, Yb3+ decreased s values to more positive values than-80 mV. In total, Yb3+ did not change the process of activation, but impelled inactivated process. Yb3+ mainly increased the Na+ current through changing its conductance. It might be one of the mechanisms that Yb3+ affected the hippocampal neurons.
文摘We reported a passive Q-switched diode laser pumped Yb: YAG microchip laser with an ion-implanted semi-insulating GaAs wafer. The wafer was implanted with 400-keV As+ in the concentration of 1016 ions/cm2. To decrease the non-saturable loss, we annealed the ion-implanted GaAs at 500℃ for 5 minutes and coated both sides of the ion-implanted GaAs with antireflection (AR) and high reflection (HR) films, respectively. Using GaAs wafer as an absorber and an output coupler, we obtained 52-ns pulse duration of single pulse.
基金partially supported by the National Basic Research Program of China (Nos.2015CB352005 and 2012CB825802)the National Natural Science Foundation of China (Nos.61378091 and 61405123)the Shenzhen science and Technology Project (No.JCYJ2015032414171561)
文摘The use of red light or near-infrared radiation as a luminescent probe for in vivo bio imaging is crucial in order to restrict the strong absorption of short-wavelength light below 600 nm in tissue. It is demonstrated that the emission color of Yb/Ho codoped NaYFa nanoparticles can be tuned from green to red by incorporating Ce3＋ ions. However, compared with that of the NaYF4：Yb/Ho nanoparticles, the photoluminescence intensity of the Ce3＋-tridoped NaYF4：Yb/Ho nanoparticles is drastically reduced. In this work, Ce3＋-incorporated core/shell NaYF4： Yb3＋50%@NaYF4：Ho3＋0.5% nanoparticles are prepared. A strong red emission and a high-intensity ratio between the red emission and green emission are obtained in these upconversion nanoparticles. The emission intensity in- creases by a factor higher than 120 when compared with that of the NaYF4 ：Yb/Ho/Ce nanoparticles. This result indicates that the Ce3＋ incorporation into the NaYF4：Yb/Ho nanoparticles promotes a strong quenching effect and reduces the emission intensity; however, the quenching effect can be significantly reduced by incorporating the Ce3＋ ions into the core/shell NaYF4：yb3＋50%@NaYF4：Ho3＋0.5% nanoparticles. A theoretical model is proposed to explain the presence of the quenching effect in the NaYF4：Yb/Ho/Ce nanoparticles, demonstrating that the quenching is mainly related to the interaction between the Yb3＋ and Ce3＋ ions.
