类锂离子(Z=11～20)1s23p-1s2nd(n=6,7)的跃迁能和振子强度

用全实加关联(FCPC)方法计算类锂离予体系(Z=11～20)1s2nd(n=6,7)态的非相对论能量.相对论及质量极化效应对能量的修正用微扰论计算,量子电动力学(QED)修正利用有效核电荷方法估算.在此基础上计算了1s23p-1s2nd(n=6,7)的跃迁能及振子强度,对现有的关于1s2nd(n=6,7)态的精细结构的实验数据的可靠性提出质疑.     

Ionization energies and term energies of the ground states ls22s of lithium-like systems

We extend the Hamiltonian method of the full-core plus correlation （FCPC） by minimizing the expectation value to calculate the non-relativistic energies and the wave functions of ls22s states for the lithium-like systems from Z = 41 to 50. The mass-polarization and the relativistic corrections including the kinetic-energy correction, the Darwin term, the electron-electron contact term, and the orbit-orbit interaction are calculated perturbatively as first-order correction. The contribution from quantum electrodynamic （QED） is also explored by using the effective nuclear charge formula. The ionization potential and term energies of the ground states 1 s22s are derived and compared with other theoretical calculation results. It is shown that the FCPC methods are also effective for theoretical calculation of the ionic structure for high nuclear ion of lithium-like systems.     

CⅠ等电子序列离子组态能量Z相关修正的改进

以相对论多体微扰理论为基础,利用屏蔽理论的思想和方法,引入并改进了与核电荷数Z相关的能量修正函数,计算了CⅠ等电子序列离子（6<=Z<=55）基组态(1s2 2s2 2p2)和第一激发组态(1s2 2s2 2p1)能量.计算过程基于自编的C语言和Mathematica程序,所得结果与实验值符合的很好,大大减小了由于忽略能量高阶项产生的误差,证明此项改进适用于等电子序列离子组态能量的计算.     

氦原子低激发态能量的变分计算

给出了一种用变分法计算氦原子低激发态（电子组态为1s2s,1s2p)能量的具体方法,计算过程中解决了激发态波函数与基态波函数的正交性,计算结果与实验值与相当接近。     

Ca原子4s2-4s4p电子碰撞激发特性

基于全相对论扭曲波（RDW）电子碰撞激发计算程序REIE06,系统计算了Ca原子基态3p64s2 1S0到激发态3p64s4p 3P0,1,2 1P1精细结构能级的碰撞截面,总结了在不同入射电子能量下碰撞截面的变化规律。目前计算中,细致考虑了电子关联效应和Breit相互作用,计算结果与已有的理论计算进行比较,对实验值的相对误差较小。     

RhⅩⅢ，PdⅩⅣ和AgⅩⅤ离子4s^24p^3-4s^24p^25s跃迁的扩展分析

用相对论Hartree-Fock方法对YⅦ-AgⅩⅤ离子4s^24p^3和4s^24p^25s组态的能级结构进行了系统的理论计算．通过分析能级结构的slater径向积分参数沿等电子序列的变化规律，运用参数拟合外推（或内插）的方法计算了上述离子组态的能级结构参数．在此基础上，计算了RhⅩⅢ，PdⅩⅣ和AgⅩⅤ离子4s^24p^3（^4S2/3，^2P1/2,3/2,^D1/2,3/2）和4s^24p^25s（^4P1/2，3/2,5/2,^2P1/2,3/2,^D2/3,5/2,^2S1/2）组态的精细结构能级以及这两个组态之间电偶极允许跃迁的全部35条谱线波长与相应的振子强度，其中PdⅩⅣ和AgⅩⅤ离子的所有数据纯属目前的预测计算值。     

Rh XⅢ—Cd XVI离子4s24p3—4s4p4能级与跃迁的理论计算

用HFR（Hartree-Fock with relativistic corrections）方法对Rb V—Cd XVI离子4s²4p³和4s4p⁴组态能级结构做了全面系统的理论计算研究. 通过分析能级结构参数的HFR理论计算值与基于实验能级拟合得到的计算值之比值随着原子序数Z_c变化的规律,运用广义拟合外推方法预言了这些离子能级结构参数. 由此进一步计算了Rh XⅢ,Pd XIV,Ag XV和Cd XVI离子4s²4p³（⁴S_3/2,²P_1/2,3/2,²D_3/2,5/2）和4s4p⁴（⁴P_1/2,3/2,5/2,²P_1/2,3/2,²D_3/2,5/2,²S_1/2）组态能级以及电偶极跃迁波长与振子强度. 研究表明,对于4s²4p³组态,单组态近似可以得到较满意的结果;而对于4s4p⁴组态,只有在考虑了4s²4p²4d的组态相互作用效应时,计算结果的准确性才能明显得到提高. 同时,本文还运用全相对论grasp2K-DEV程序包计算了Rh XⅢ—Cd XVI离子组态能级. 对于Rh XⅢ离子4s²4p³（²P_1/2）,Pd XIV离子4s²4p³（⁴S_3/2,²P_1/2,3/2,²D_3/2,5/2）和4s4p⁴（²P_1/2,3/2,²D_3/2,5/2,²S_1/2）,能级均无实验值;对于Ag XV和Cd XVI离子,截至目前还没实验能级数据,没有实验能级值的所有数据均仅来自本文的计算数值. 本文计算结果与已有实验值吻合得很好.     

类锂体系(Z=21-30)基态1s22s电离能和相对论项能的理论计算

使用全实加关联方法和里兹(Ritz)变分方法计算了类锂体系(Z=21-30)基态1s22s的非相对论能量和波函数;包括动能修正、电子-电子接触项、轨道-轨道相互作用项以及Darwin项的相对论修正和质量极化项由全实加关联波函数的一阶微扰给出,量子电动力学修正QED(quantum electronic dynamic)由有效核电荷方法和类氢公式计算;给出了中等核电荷的高电离类锂体系基态的电离能、相对论效应的项能(term energy),并将计算结果与实验数据进行了比较,表明FCPC方法对于较高核电荷类锂体系结构的理论计算仍然十分有效.     

弛豫与关联效应对NII离子2s22p3s3P1—2s22p21D2与2s22p3s1P1—2s22p23P0,1,2自旋禁戒跃迁概率的影响

用多组态Dirac-Fock方法，并系统考虑相对论效应、电子关联、弛豫效应等重要贡献，计算了NII离子2s22p3s 3P1—2s22p21D2和2s22p3s 1P1—2s22p23P0,1,2自旋禁戒跃迁概率和振子强度-通过比较计算证实：弛豫和关联效应对禁戒跃迁概率的影响非常大，考虑了这些效应后，计算结果有显著的改善-由跃迁概率和振子强度的计算值推断，2s22p3s 3P1—2s22p21D2的谱线强度应该比原有的理论预言值小- 关键词： 跃迁概率 多组态Dirac-Fock方法     

类锂体系(Z=21—30)基态1s22s电离能和相对论项能的理论计算

使用全实加关联方法和里兹(Ritz)变分方法计算了类锂体系(Z=21—30)基态1s²2s的非相对论能量和波函数；包括动能修正、电子-电子接触项、轨道-轨道相互作用项以及Darwin项的相对论修正和质量极化项由全实加关联波函数的一阶微扰给出，量子电动力学修正QED(quantum electronic dynamic)由有效核电荷方法和类氢公式计算；给出了中等核电荷的高电离类锂体系基态的电离能、相对论效应的项能(term energy)，并将计算结果与实验数据进行了比较，表明FCPC 关键词： 类锂体系 全实加关联 电离能 项能     

多段阵列式放大器特性的计算模拟

考虑了从电容器储能到激光介质储能的多个能量转换环节,引入时间因子和三维空间放大自发辐射,对多段阵列式放大器９ＭＳＡ）性能作了详细的计算模拟,包括多段阵列式放大器的中间和边缘闪光阵列间的泵浦平衡、储能、增益系数和增益分布等重要激光参数随时间的变化,利用利弗莫尔实验室的实验参数对本文的程序进行了校核,并演示了该程序的预估能力。     

Tm3+/Ho3+共掺碲酸盐玻璃的2.0μm发光特性及能量传递

研究了Tm³⁺/Ho³⁺共掺TeO₂-WO₃-ZnO玻璃在808 nm激光二极管抽运下的2.0μm发光特性及Tm³+与Ho³⁺之间的能量传递.应用Judd-Ofelt理论计算了Ho³⁺在碲酸盐玻璃中的谱线强度参量Ω_t (t=2,4,6)、自发辐射概率A_r、辐射寿命τ_r等.计算了Ho³⁺的吸收截面σ_a(λ)和受激发射截面σ_e(λ).结果表明：碲酸盐玻璃中Tm³⁺→Ho³⁺正向能量传递系数大约是Tm³⁺←Ho³⁺反向能量传递系数的18倍.Ho³⁺离子的⁵I₇能级的寿命为3.9ms，2.0μm处的最大发射截面为9.15×10^-21cm².在0.5mol% Tm₂O₃和0.15mol% Ho₂O₃共掺的碲酸盐玻璃中能获得2.0μm的最大增益.通过比较氟化物、碲酸盐和镓铋酸盐重金属氧化物等玻璃中Ho³⁺的量子效率η，σ_e×τ_m值和增益系数G(λ)等，发现Tm³⁺/Ho³⁺共掺碲酸盐玻璃是一种理想的2.0μm激光器用基质玻璃. 关键词： 2.0μm发光 能量传递 增益 碲酸盐玻璃     

关于磁单极子的探索

磁单极子的概念自狄拉克提出以来,科学家一直都在努力寻找。虽然在理论上进行了深入的研究,但是在实验中,迄今仍然没能找到它们存在的确凿证据。文章从麦克斯韦方程组的对称性及电荷量子化的角度介绍了磁单极子的提出,磁单极子的单位及性质。并介绍了关于磁单极子的实验探索,除了历史上著名的两次实验外,科学家还在自旋冰中观察到磁单极子的“准粒子”。     

A generalization of the inhomogeneity measure for point distributions to the case of finite size objects

The statistical measure of spatial inhomogeneity for n points placed in χ cells each of size k×k is generalized to incorporate finite size objects like black pixels for binary patterns of size L×L. As a function of length scale k, the measure is modified in such a way that it relates to the smallest realizable value for each considered scale. To overcome the limitation of pattern partitions to scales with k being integer divisors of L, we use a sliding cell-sampling approach. For given patterns, particularly in the case of clusters polydispersed in size, the comparison between the statistical measure and the entropic one reveals differences in detection of the first peak while at other scales they well correlate. The universality of the two measures allows both a hidden periodicity traces and attributes of planar quasi-crystals to be explored.     

使用α粒子轰击天然镱靶制备~(178m2)Hf同质异能素及样品γ能谱分析

178m2Hf是一种长半衰期(T1/2=31 a)、高自旋态(Iπ=16+)的Hf同质异能素.利用四川大学CS-30回旋加速器产生的30 MeV,100μA的α束流轰击天然Yb靶,通过176Yb(α,2n)反应制备178m2Hf.采用高纯Ge探测器测量未提纯样品和放化分离后的样品的γ能谱,选取178m2Hf的426,495和574 keV三个特征峰,使用高斯双峰拟合方法解谱,确定了未提纯样品中178m2Hf的含量达到1012量级,提纯后的样品中178m2Hf含量为1011量级.还对靶中其他放射性杂质核素(175Hf,172Lu,172Hf,177Lu,173Lu)的含量进行了分析.     

Effects of chlorine gas exposure on the optical properties of rhodium phthalocyanine films

We investigated the effects of exposing rhodium phthalocyanine films deposited on glass substrates by the Lagmuir-Blodgett technique to chlorine gas. The visual aspect of the films is altered upon chlorination, changing in color from blue to transparent. We performed optical absorption and Raman Scattering measurements on our films prior to and after exposing it to chlorine gas. We observed a pronounced quenching of the characteristic triplet centered around the Q-absorption band at 662 nm as a result of chlorine incorporation. Another absorption band, in the near UV part of the spectrum, is not greatly affected by the process. No new optical structures appear as a consequence of chlorination. Equivalent effects were observed in the Raman spectra. Leaving the previously exposed films in air for several hours results in a slow partial recovery of the optical spectra. This recovery, as well as the amount of original quenching, depends on the amount of time during which the film was exposed to chlorine.     

Reissner-Nordstr?m de Sitter黑洞的量子隧穿效应

运用Parikh的量子隧穿模型，研究了Reissner-Nordstrm de Sitter黑洞的量子隧穿效应.结果表明，在能量守恒的条件下，黑洞外视界和宇宙视界处的粒子出射率与Bekenstein-Hawking熵有关，辐射谱不再是严格的纯热谱.     

Characterization of thermal, optical and carrier transport properties of porous silicon using the photoacoustic technique

In this work, the porous silicon layer was prepared by the electrochemical anodization etching process on n-type and p-type silicon wafers. The formation of the porous layer has been identified by photoluminescence and SEM measurements. The optical absorption, energy gap, carrier transport and thermal properties of n-type and p-type porous silicon layers were investigated by analyzing the experimental data from photoacoustic measurements. The values of thermal diffusivity, energy gap and carrier transport properties have been found to be porosity-dependent. The energy band gap of n-type and p-type porous silicon layers was higher than the energy band gap obtained for silicon substrate (1.11 eV). In the range of porosity (50-76%) of the studies, our results found that the optical band-gap energy of p-type porous silicon (1.80-2.00 eV) was higher than that of the n-type porous silicon layer (1.70-1.86 eV). The thermal diffusivity value of the n-type porous layer was found to be higher than that of the p-type and both were observed to increase linearly with increasing layer porosity.     

On the gate- and drain-voltage dependence of the RTS amplitude in submicron MOSTs

The experimental gate- (V _GS) and drain-voltage (V _DS) dependence of the fractional Random Telegraph Signal (RTS) amplitude I _D/I _D, obtained on a large series of submicron Metal-Oxide Semiconductor Transistors (MOSTs), is reported. The observed variation of the RTS amplitude in linear operation is discussed in view of recently published models. As will be shown, the large spread in weak-inversion amplitudes can only be explained by taking into account the microscopic nature of the oxide trap and its environment. The position of a trap along the channel can in principle be retrieved from studying the so-called RTS amplitude asymmetry, defined as the V _DS dependence of the amplitude in both normal and reverse operation of the transistor. Widely different asymmetry behaviour is observed in this work. Here, a qualitative model will be derived which gives a more refined analysis and offers some deeper insight than existing theories. However, to fully understand the RTS amplitude in weak inversion, more microscopic detail is needed.     

Modulation of the photoluminescence of Si quantum dots by means of CO2 laser pre-annealing

Si quantum dots (QDs) embedded in SiO₂ can be normally prepared by thermal annealing of SiO_x (x < 2) thin film at 1100 °C in an inert gas atmosphere. In this work, the SiO_x thin film was firstly subjected to a rapid irradiation of CO₂ laser in a dot by dot scanning mode, a process termed as pre-annealing, and then thermally annealed at 1100 °C for 1 h as usual. The photoluminescence (PL) intensity of Si QD was found to be enhanced after such pre-annealing treatment. This PL enhancement is not due to the additional thermal budget offered by laser for phase separation, but attributed to the production of extra nucleation sites for Si dots within SiO_x by laser irradiation, which facilitates the formation of extra Si QDs during the subsequent thermal annealing.