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1.
王耀祥  马成义 《光子学报》2000,29(3):260-263
本文讨论了在硼硅酸盐玻璃系统中引入二价Ba2+、Pb2+和四价Ti4+后,由于Pb2+和Ti4+配位结构的变化,引起Pb2+、Ti4+场强及其与O2-离子间距的变化,对Li+/Na+离子交换产生影响,从而改变折射率差值(ΔN)和折射率分布.  相似文献   

2.
本文应用复合粒子量子场论的微扰展开式和相对论性的(π&;#177;μ?)、(K&;#177;μ?)的B.S.波函数,计算了在原子核屏蔽库仑场中高能(π&;#177;μ?)、(K&;#177;μ?)原子的裂解能谱和截面。在极端相对论近似下,对大多数原子核,它们的裂解截面分别约为10-18cm2和10-17cm2。利用同样的波函数,还计算了(π&;#177;μ?)→π0+vμ(vμ),(K&;#177;μ?)→K0+vμ(vμ),以及(π&;#177;μ?)→μ+-+vμ(vμ),(K&;#177;μ?)→μ+-+vμ(vμ)的衰变几率。  相似文献   

3.
黄妙良  许承晃 《光子学报》1995,24(4):289-292
文中报进了有关辅助光对NaCl(OH-):(F2+)H及KCl(Na+,OH-):(F2+)AH色心激光输出功率影响的主要研究结果。初步探讨了辅助光作用的物理机制。  相似文献   

4.
We calculate the branching ratios of pure annihilation type decays B0→Ds- K2*+ and Bs→Da2 using the perturbative QCD approach based on kT factorization. The branching ratios are predicted to be (60.6-16.5-10.4-2.1+17.3+4.3+3.2 )× 10-6 for B0→Ds- K2*+, (1.1-0.4-0.2-0.1+0.4+0.1+0.1)×10-6 for Bs→D0a20 and (2.3-0.8-0.4-0.1+0.8+0.2+0.1)×10-6 for Bs→D-a2+. They are large enough to be measured in the ongoing experiment. Due to the shortage of contributions from penguin operators, there are no direct CP asymmetries for these decays in the Standard Model. We also derive simple relations among these decay channels to reduce theoretical uncertainties for the experiments to test the accuracy of theory and search of new physics signal.  相似文献   

5.
Motivated by the rst measurement on B(Bs→φμ+μ-) by the CDF Collaboration, we study the supersymmetric e ects in semi-leptonic Bs→φμ+μ- decay. In our evaluations, we analyze the dependences of the dimuon invariant mass spectrum and the forward-backward asymmetry on relevant supersymmetric couplings in the MSSM with and without R-parity. The analyses show that the new experimental upper limits of B(Bs→φμ+μ-)from the LHCb Collaboration could further improve the bounds on sneutrino exchange couplings and (δLLu)23 as well as (δLL,RRu)23 mass insertion couplings. In addition, within the allowed ranges of relevant couplings under the constraints from B(Bs→φμ+μ-), B(B→K(*)μ+μ-) and (Bs→φμ+μ-), the dimuon forward-backward asymmetry and the di erential dimuon forward-backward asymmetry of Bs→φμ+μ-are highly sensitive to the squark exchange contribution and the (δLLu)23 mass insertion contribution. The results obtained in this work will be very useful in searching for supersymmetric signals at the LHC.  相似文献   

6.
K+-Na+二次离子交换制作玻璃波导   总被引:4,自引:4,他引:0  
黄腾超  沈亦兵  侯西云  侯昌伦  白剑 《光子学报》2003,32(11):1325-1328
通过数值计算模拟了K+Na+二次扩散玻璃波导的折射率轮廓,阐述了利用K+Na+二次离子交换的方法,在BK7玻璃上制作波导的过程,分析了极化率不同的扩散离子对的选择对波导有效折射率变化的影响,以及扩散平衡时体积变化对表面折射率的影响,描述了扩散引起的波导内部诱导应力变化设计了测试波导损耗以及波导表面折射率改变的实验装置,对尺寸10mm×10mm×1.5mm和10mm×5mm×1.5mm两组BK7玻璃基片上的玻璃波导进行了测试,测试结果与理论吻合较好.  相似文献   

7.
In a combined investigation of B→K(*)l+l- decays, constraints on the related couplings in family non-universal Z' models are derived. We find that within the allowed parameter space, the recently observed forward-backward asymmetry in the B→K(*)l+l- decay can be explained by flipping the signs of the Wilson coefficients C9eff and C10. With the obtained constraints, we also calculate the branching ratio of the Bs→μ+μ- decay. The upper bound of our prediction is nearly an order of magnitude smaller than the upper bound given by the CDF Collaboration recently.  相似文献   

8.
文中,针对X形谐振腔的特点及结合纵向泵浦理论,分析了X形谐振腔几何参数的确定条件和模式匹配条件;根据有关NaCl(OH-):(F2+)H和KCl(Na+,OH-):(F2+)AH色心激光的主要研究结果,分析了提高色心激光输出效率的可能途径.  相似文献   

9.
王伟  吕才典 《中国物理 C》2008,32(10):773-775
We investigate the D0-D0 mixing through the doubly Cabibbo suppressed (DCS) channel D0→f0(980)K*0 and its charge conjugate channel, in which the K*0 meson is reconstructed in both K+π and K0 final state. Although the decay D0→f0(980)K* has a small branching ratio, the final state mesons are relatively easy to identify. The f0(980) meson can be replaced by the S-wave π+π state, or a longitudinally polarized vector meson ρ0. All mixing parameters, including the mass difference and decay width difference, can be extracted by studying the time-dependent decay width of these channels. We show that the method is valid in all regions for mixing parameters and it does not depend on the strong phase difference.  相似文献   

10.
聂秋华  高媛  徐铁峰  沈祥 《光子学报》2005,34(5):773-777
制备了Er3+/Yb3+共掺的70TeO2-5Li2O-(25-x)B2O3-xGeO2(x=0,5,10,15,20 mol%)系列玻璃, 研究了玻璃的热稳定性能, 测试了玻璃的吸收光谱、荧光光谱以及Er3+离子4I13/2能级荧光寿命, 并根据McCumber理论计算了Er3+离子4I13/2→4I15/2跃迁的受激发射截面. 结果表明:随着GeO2含量的增加, 玻璃的热稳定性逐渐提高, 荧光谱线半高宽(FWHM)保持在70 nm左右, 而荧光强度和Er3+离子4I13/2能级荧光寿命逐渐提高, 研究表明这种玻璃系统是一种具有应用潜能的宽带光纤放大器用的基质材料.  相似文献   

11.
Eu3+在硼酸盐玻璃中的发光以及Bi3+对Eu3+的敏化作用   总被引:7,自引:1,他引:6  
李宝祥  张振江 《发光学报》1991,12(3):238-243
本文研究了单掺和双掺(Eu3+,Bi3+,Fu3++Bi3+)约二十余种不同成份的硼酸盐玻璃,探讨了玻璃成份对Eu3+发光性质的影响和Bi3+对Eu3+的敏化作用.  相似文献   

12.
玻璃波导及两次离子交换法   总被引:3,自引:1,他引:2  
沈荣桂 Righ.  GC 《光学学报》1991,11(6):58-563
本文报道Soda-lime玻璃的Ag~+-Na~+和K~+-Na~+离子交换波导的制备、特性分析;并介绍制作表面折射率元件(例如棱镜、透镜)的两次离子交换法,以及用卢瑟福后向散射谱分析玻璃离子交换后表面层的离子分布轮廓。  相似文献   

13.
Er3+,Yb3+共掺磷酸盐玻璃沟道波导放大器   总被引:11,自引:6,他引:5  
在自行研制的Er3 ,Yb3 共掺磷酸盐玻璃基质上用离子交换方法制作出沟导光波导放大器。在110mW的抽运功率下(抽运光波长为980nm),在1.8cm长的器件上获得了3.8dB的小信号(信号光波长为1.55μm)增益,单位长度上的增益为2.1dB/cm。  相似文献   

14.
李宝祥  韩尧 《发光学报》1993,14(1):53-60
本文研究了单掺(Sm3+,Ce3+、Gd3+.Sb3+、双掺(Sm3++Ce3+、Sm3++Gd3+,Sm3++Sb3+)和兰掺(Sm3++Gd3++Ce3+)约四十余种不同玻璃的发射谱和激发谱.探讨了玻璃成份和掺杂离子浓度对Sm3+发光性质的影响以及Ce3+,Gd3+、Sb3+、Ce3++Gd3+对Sm3+的敏化作用。  相似文献   

15.
王Jie  明海 《发光学报》1996,17(2):104-110
本文研究了氟锆酸盐玻璃中Tm3+与Er3+的能量转移,在不同激发彼长激发下,能量转移的机制有不同之处。Tm3+对Er3+的作用表现在使得2H11/24S3/2的发光减弱,4F9/24I11/2的发光增加,即将Er3+高能级的粒子搬运至低能态上。在一定条件下甚至可以完全猝灭4S3/2的荧光。  相似文献   

16.
干福熹  邓和  刘慧民 《物理学报》1982,31(3):410-414
低温77K下,在三种玻璃中都观察到了Co2+的ESR信号,认为Co2+是处干四面体格位,从实验所得的有效g值,判别出中心离子与配位体间化学键的性质变化,本文还研究了氟磷酸盐玻璃中Ni2+ESR,辨认了Ni2+的谱线,用自旋哈密顿作了比较详细的分析计算,并解释了一般氧化物玻璃中很难观察到Ni2+的ESR的原因。 关键词:  相似文献   

17.
大尺寸轴向梯度折射率光学玻璃板的研制   总被引:4,自引:0,他引:4  
霍军民  李育林 《光子学报》2003,32(10):1278-1280
研制了一种含钠光学玻璃和另一种含铊光学玻璃材料,并用离子交换方法使钠玻璃中钠离子与银盐中银离子交换;铊玻璃中铊离子与钾盐中钾离子交换,获得了两种高折射率梯度的轴向分布光学板.  相似文献   

18.
用荧光分光光度法研究了Zn2+,Mn2+,Cd2+,Na+,K+,Ag+,Cu2+和Pb2+等金属离子修饰的ZnS/PAMAM树形分子纳米复合材料的荧光发射性能。结果表明:不同金属离子修饰效果不同。Zn2+,Mn2+和Cd2+修饰后,ZnS/PAMAM树形分子纳米复合材料的荧光发射强度有不同程度提高;Ag+,Cu2+和Pb2+的修饰对荧光有不同程度的猝灭作用;而Na+和K+的修饰对荧光发射无明显影响。与修饰前相比,Cd2+离子修饰的ZnS/PAMAM树形分子纳米复合材料标记的潜指纹发射的蓝色荧光更加明亮,与背景反差更加明显。这对提高潜指纹的显现精度和准确率有很好的借鉴价值。  相似文献   

19.
Optical absorption, emission and excitation spectra, lifetimes of 4S3/2 state and 4F9/2 state from 10K to 500K, and Raman spectra were measured for Er3+ ions in fluoride glass. The radiative transition probabilities were calculated on the basis of Judd-Ofelt theory. The nonradiative transition probabilities and the quantum efficiencies were determined by calculating the difference between the measured lifetimes and the calculated radiative transition probabilities. The temperature dependence of nonradiative transition provavility was investigated using the Huang-Rhys theory of multiphonon relaxation , in which two kinds of phonons as well as the parameter s were taken into consideration. A fairly good agreement of the theoretical calculation with the experimental results has been obtained. The value of s is estimated and the effect of s is discussed.  相似文献   

20.
运用拉曼光谱技术研究了Na2O(K2O)—CaO(MgO)—SiO2,Na2O(K2O)—Al2O3—SiO2,Na2O(K2O)—B2O3—SiO2,Na2O(K2O)—PbO—SiO2和PbO—BaO—SiO2五个系统的玻璃。结果表明,阳离子对玻璃近程结构的改造会引起拉曼特征的变化。部分样品是根据古玻璃平均成分在实验室烧制的,这项研究对于运用激光拉曼光谱区分不同系统的古代硅酸盐玻璃有重要意义。  相似文献   

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