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41.
采用高温固相法制备系列红色荧光粉Naz Ca1-x-2y-zBiyMoO4 ∶ Eu3+x+y (y,z=0,x=0.24,0.26,0.30,0.34,0.38; x=0.30,y=0.01,0.02,0.03,0.04,0.05,0.06,0.07,z=0; x=0.30,y=0.04,z=0.38).用X射线粉末衍射(XRD)法测试了所制样品晶相结构.采用荧光光谱仪对样品的发光性能进行了表征,结果表明:当Eu3+单掺杂量浓度x=0.30时,荧光粉(Ca0.70 MoO4∶Eu3+0.30)的发光强度最强;当Eu3+-Bi3+共掺杂量浓度y=0.03时,电荷迁移带(CTB)强度达到最强,而对于Eu3+特征发射峰,当共掺杂浓度y<0.03时,位于393 nm处的激发峰强度比464 nm强,共掺浓度y>0.03时,464 nm峰比393 nm峰强,共掺浓度为y=0.04时,393和464 nm处两峰位置强度都达到最强.作为电荷补尝剂的Na2 CO3掺入上述荧光粉中后,荧光粉激发和发射强度明显地增强.结果表明,通过调节Bi3+ /Eu3+掺杂比例可以改变位于近紫外光393 nm和蓝光区464 nm处激发光相对强度. 相似文献
42.
43.
A 2.048μm Tm,Ho:GdVO4 Laser Pumped Doubly Resonant Optical Parametric Oscillator Based on Periodically Poled Lithium LiNbO3 下载免费PDF全文
A multi-grating periodically poled LiNb03 (PPLN) doubly resonant optical parametric oscillator (DROPO) pumped by a 2-ttm laser is demonstrated experimentally. Employing acousto-optically Q-switched Tm,Ho:GdV04 laser with pump pulse of 25ns and repetition rate of lOkHz as pump sources firstly, the noncritically quasi- phase-matched (QPM) tunable mid-IR output in 3.87-4.43 μm is produced. Wavelength tuning is achieved with crystal temperature tuning from 50-180^o C. When the incident average pump power is 3 W at 2.048μm, the total OPO output power of 195mW at wavelength 3.88μm is obtained, corresponding to optical-to-optical conversion efficiency up to 6.5%. 相似文献
44.
JU Guo-Xing CAI Chang-Ying REN Zhong-Zhou 《理论物理通讯》2009,51(5):797-802
We study the generalized harmonic oscillator that has both the position-dependent mass and the potential depending on the form of mass function in a more general framework. The explicit expressions of the eigenvalue and eigenfunction for such a system are given, they have the same forms as those for the usual harmonic oscillator with constant mass. The coherent state and its properties corresponding effective potentials for several mass functions, for the system with PDM are also discussed. We give the the systems with such potentials are isospectral to the usual harmonic oscillator. 相似文献
45.
在CdTe太阳电池中,易引入并形成Cu深能级中心. 本文采用深能级瞬态谱测试法研究了ZnTe背接触和石墨背接触CdTe太阳电池的部分深能级中心. 研究中运用密度泛函相关理论,分析闪锌矿结构CdTe,Cd空位体系和掺Cu体系的电子态密度,计算得出Td场和C3v场下Cu2+ d轨道的分裂情况. 计算结果表明,CdTe太阳电池中的Ev+0206 eV和Ev+0122 eV两个深中心来源于Cu替代Cd原子. 计算结果还表明,掺入Cu可降低CdTe体系能量.
关键词:
深能级瞬态谱
第一性原理
CdTe
Cu杂质 相似文献
46.
Deterministic Assisted Clone of an Arbitrary Two- and Three-qubit States via Multi-qubit Brown State
Kui Hou Cheng-Jie Zhu Ya-Ping Yang 《International Journal of Theoretical Physics》2017,56(8):2588-2600
We present two schemes for deterministic assisted clone(DAC) of an unknown two- and three-qubit entangled states with assistance via muti-qubit Brown state. In the schemes, the sender wish to teleport an unknown original entangled state which from the state preparer, and then create a perfect copy of the unknown state at her place. The DAC schemes include two stages. The first stage requires teleportation with Bell-state measurements via a five-qubit Brown state(or seven-qubit Brown state) as the quantum channel. In the second stage, to help the sender realize the quantum cloning, the state preparer performs projective measurements on their own particles which from the sender, then the sender can acquire a perfect copy of the unknown state by means of some appropriate unitary operations. Furthermore, the total success probability for assisted cloning a perfect copy of the unknown state can reach 1 in our schemes. 相似文献
47.
利用溶胶凝胶方法在石英玻璃衬底上制备了ZnO薄膜,将能量56 keV、剂量1×1017 cm-2的Zn离子注入到薄膜中。离子注入后,薄膜在500~900 ℃的氩气中退火,利用X射线衍射谱、光致发光谱和光吸收谱研究了离子注入和退火对ZnO薄膜结构和光学性质的影响。结果显示:衍射峰在约700 ℃退火后得到恢复;当退火温度小于600 ℃时,吸收边随着退火温度的提高发生蓝移,超过600 ℃时,吸收边随着退火温度的提高发生红移;近带边激子发光和深能级缺陷发光都随退火温度的提高而增强。 相似文献
48.
The focusing of time reversal acoustic fields for dispersive and multimodal Lamb waves is theoretically investigated and experimentally verified. It is demonstrated that the time reversal Lamb wave signal will reach the maximum amplitude when the observation point is located at the damage location. Based on the time reversal focusing theory, a damage imaging method is proposed for structural health monitoring using Lamb waves. The experiments employ a transducer network consisting of four piezoelectric transducers as actuators and as well sensors for excitation and measurement of Lamb waves. The results show that this method is able to accurately predict damage location and provides an estimation of the possible area even for damage close to one of the transducers or even slightly outside the transducer network. 相似文献
49.
Optical Properties of Co-BaTiO3/Mg(100) Nano-Composite Films Grown by Pulsed Laser Deposition Method 下载免费PDF全文
Co nanoparticles embedded in a BaTiO3 matrix, namely Co-BaTiO3 nano-composite films are grown on Mg(100) single crystal substrates by the pulsed laser deposition (PLD) method at 650℃. Optical properties of the CoBaTiO3 nano-composite films are examined by absorption spectra (AS) and photoluminescence (PL) spectra. The results indicate that the concentration of Co nano-particles strongly influences the electron transition of the Co BaTiO3 nano-composite films. The PL emission band ranging from 1.9 to 2.2eV is reported. The AS and PL spectra suggest that the band gap is in the range of 3.28-3.7eV. 相似文献
50.
An overview of research status of soft physics in high energy heavy-ion collision experiments and recent experimental results are presented. This paper includes four parts: 1) Theoretical predictions of quark-gluon plasma and introduction for high energy heavy ion collision experiments. 2) Experimental status on collision 相似文献