奇奇核162Lu晕转带及四准粒子带的能级结构

通过在束谱学实验方法建立了¹⁶²Lu的晕转带及四准粒子带的能级纲图. 依据推转壳模型指出,正γ变也会导致Z=71奇奇核¹⁶²Lu的晕转带发生低自旋signature反转.     

FTIR—PAS技术在卟啉类化合物中的应用（IV）：稀土乙酰丙酮—me…

研究了ｍｅｓｏ－四－（α－萘基）四苯并卟啉及其Ｄｙ，Ｈｏ，Ｅｒ，Ｔｍ，Ｙｂ，Ｌｕ乙酰丙酮形成的配合物在３６００￣２２０ｃｍ＾－１范围内的傅里叶变换红外光声光谱（ＦＴＩＲ－ＰＡＳ），对主要谱带进行了经验归属。结果表明，四－（α－萘基）四苯并卟啉与稀土乙酰丙酮配合物中稀土金属离子配位削弱了乙酰丙酮环上Ｍ－Ｏ键的伸缩振动，使此谱带向低波数位移。金属敏感谱带出现在￣１５１３，￣１３２３￣１０９０，１０５３     

介质阻挡放电系统中带晕蜂窝六边形发光斑图

为了丰富介质阻挡放电系统中斑图的多样性,利用双水电极介质阻挡放电装置,在空气和氩气按一定比例混合的气体中（氩气含量χ=25%）,发现了带晕蜂窝六边形斑图。通过观察用普通相机拍摄的斑图照片,可以发现斑图是由中心点、晕和蜂窝框架构成,且中心点位于晕的中心,中心点和晕嵌套在蜂窝框架的中心。采用带有3个通道的高速照相机对斑图进行分脉冲瞬态拍摄,结果显示带晕蜂窝六边形斑图的3套子结构在外加电压的半周期内,总是按照晕-蜂窝框架-中心点这样的顺序放电。运用光电倍增管对这3套子结构进行研究,发现晕的放电在时间和空间上具有局部选择性。利用发射光谱法,根据氮分子第二正带系（C³Π_u→B³Π_g）谱线计算了中心点、晕和蜂窝框架的分子振动温度,结果显示:中心点的分子振动温度为2 632 K,晕的分子振动温度为2 679 K,蜂窝框架的分子振动温度为2 720 K。本文利用壁电荷理论解释带晕蜂窝六边形斑图的形成机制和时空结构。     

~（171）Lu1／2~－［541］轨道的形变驱动作用

通过熔合蒸发反应１６０Ｇｄ（１９Ｆ，６ｎ２ｐ）对１７１Ｌｕ的１／２－［５４１］转动带进行了研究，观测到了此带的第一带交叉频率．与相邻偶偶核相比该频率值推迟了约４０ｋｅＶ．推转壳模型对单准质子的顺排角动量和能量的计算结果表明πｈ９／２［５４１］１／２－轨道的形变驱动作用对这种推迟的贡献是不应被忽略的．     

N2第一正带的塞曼调制磁旋转光谱分析

在１７０７９￣１７４０７ｃｍ＾－１范围内，利用了塞曼调制磁旋转光谱技术测量了Ｎ２分子第一正带Ｂ＾３Пｇ￣Ａ＾３Σｕ＾＋的（１０，６）、（１１，７）、（１２，８）带的近９００条谱线，其中包括了用以往各种光谱技术很难观测到的Ｐ１３、Ｑ１３、Ｒ１３和Ｐ３１、Ｑ３１、Ｒ３１支线，给出了量子态的标识，并且拟合出相应的转动分子常数。     

高自旋三轴超形变研究的新进展

高旋旋超形变研究是高自旋态物理研究中的热门课题之一。作者是在中国原子能科学研究院的ＨＩ－１３串列加速器上通过＾１５２Ｓｍ（＾１９Ｆ，４ｎ）＾１６７Ｌｕ反应观测到＾１６７Ｌｕ的一个新的转动带。     

162Lu的高自旋态及A=160区双奇核晕态能级的符号因子反转

利用¹⁴⁷Sm(¹⁹F,4nγ)¹⁶²Lu反应研究了¹⁶²Lu的高自旋态. 由7个带BGO康普顿抑制的高纯锗探测器和一个小平面探测器进行了在束γ测量,首次建立了双奇核¹⁶²Lu转晕带的能级纲图. 发现在低转动频率下,¹⁶²Lu的转晕带能级发生符号因子反转. 对质量数A=160核区双音核的转晕带重新进行了分析和考察,讨论了转晕带能级符号因子反转的系统性.     

用2△分析超带的性质

使用两准粒子能量2△计算了超带转排角动量J（I_∽）,用J（I_∽）定量地分析了一些核超带性质。     

Rb晕带signature反转的机理

将角动量投影壳模型应用到84Rb核，对组态为πg9/2νg9/2的正宇称晕带和组态为π(p3/2,f5/2)νg9/2的负宇称晕带理论计算和实验结果进行了比较，特别是对正宇称晕带中的signature反转机理进行了探讨.角动量投影壳模型计算显示正宇称晕带中的signature反转是原子核随自旋增加形状发生变化的信号，其间原子核从低自旋的长椭球通过三轴形变变到高自旋的扁椭球.此外，还确定了此两带的原子核形状.     

A≈80区奇–奇核80,82Rb的晕带能谱计算

在A≈80区奇-奇核旋称反转问题上已提出几种机制,但没有一种理论推断是结论性的.在本工作中将角动量投影壳模型应用到^80,82Rb核,对组态为πg_9/2⊙νg_9/2的正宇称晕带和组态为π(p_1/2,p_3/2,f_5/2)⊙νg_9/2 的负宇称晕带理论计算和实验结果进行了比较,特别是对正宇称晕带中的signature反转机制进行了探讨.角动量投影壳模型计算显示正宇称晕带中的signature反转是原子核随自旋增加形状发生变化的信号,其间原子核从低自旋的长椭球变到高自旋的扁椭球.此外,还确定了此两带的原子核形状     

Band filters-spectrodividers

Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 54, No. 2, pp. 295–298, February, 1991.     

Effect of Band Nonparabolicity on the Inter Band Tunneling in Semiconductors

A simple yet generalized theory is developed to study inter band tunneling property of narrow band gap III–V compound semiconductors. The band structures of these low band gap semiconductors with sufficiently separated split-off valance band are usually described by the three energy band model of Kane, so this has been adopted here for the analysis of interband tunneling property in the case of InAs, InSb, and In_1-xGa_xAs_yP_1-y lattice matched to InP as representative direct band gap semiconductors having varied split-off valence band compared to their bulk state band gap energy. It has been found that the magnitude of tunneling rate from heavy hole decreases with increasing band nonparabolicity and the impact is more significant at high electric field in the three-band model of Kane than those with simple parabolic energy band approximations reflecting the direct influence of energy band parameters on inter band tunneling transitions. With proper consideration of band nonparabolicity, the results of the analysis of tunneling rate of these narrow gap materials show significant deviations from the results when simple parabolic band approximation is considered. The exact physical basis of the sources of deviation in the nonparabolic case from the corresponding parabolic band approximations is discussed in association to band coupling effect, transverse energy dependence, and the interplay between them. Moreover, under certain limiting conditions, our results reduce to the well-known results of parabolic band approximation and thus providing an indirect test to the accuracy of our generalized formulations.     

146Ce核的八级形变带和准γ带

通过测量²⁵²Cf自发裂变所产生的瞬发γ射线, 对¹⁴⁶Ce核的高自旋结构进行了重新研究, 结果更新了以前报道的能级纲图, 把八级形变集体带扩展到更高的自旋, 并且重新构建了可能的准γ带结构. 此外, 用反射不对称壳模型(RASM)对¹⁴⁶Ce核的八级形变带进行了计算, 低自旋处的计算结果与实验数据符合得很好.     

Eigenvector Localization for Random Band Matrices with Power Law Band Width

It is shown that certain ensembles of random matrices with entries that vanish outside a band around the diagonal satisfy a localization condition on the resolvent which guarantees that eigenvectors have strong overlap with a vanishing fraction of standard basis vectors, provided the band width W raised to a power μ remains smaller than the matrix size N. For a Gaussian band ensemble, with matrix elements given by i.i.d. centered Gaussians within a band of width W, the estimate μ ≤ 8 holds.     

Band ordering in PbTe

Two possible conduction band orderings, I, L^-₆(L_2'), L^-₆(L_3'), L^-₄₅(L_3') and II, L^-₆(L_3'), L^-₄₅(L_3'), L^-₆(L_2') are considered for PbT e using the Empirical Pseudopotential method. Various properties (i.e. optical reflectivity temperature and pressure dependence of the band gap and effective masses) are considered for the two possible orderings.     

Enlargement of Photonic Band Gaps and Physical Picture of Photonic Band Structures

Light propagation in a one-dimensional photonic crystal （PC）, consisting of alternative slabs with refractive indices （layer thicknesses） nl （a） and n2 （b）, is investigated. An important optimal parameter matching condition, n1a ≈ n2b, is obtained for the largest photonic band gap （PBG）. Moreover, we find that the exact analytical solutions for the electric/magnetic field eigenmodes at the band edges are standing waves with odd or even symmetry about the centre of each layer. The electric/magnetic field eigenfunctions at the top and bottom of the nth band have n and n - 1 nodes in one period of PC, respectively. The PBG arises from the symmetric differences of the field eigenfunctions at the band edges.     

Band calculation for Ce-compounds

The results of self-consistent FLAPW calculations for Ce-compounds are presented. The crossover from dense Kondo to valence fluctuation in CeIn₃ under pressure is discussed. The small Fermi surfaces in CePd₃ explain the anomalous residual resistivity in this compound. The full potential effects in CeNi are examined.     

Band structure of AlSb

A combination of the pseudopotential method with thek. p method was used to calculate the complete band structure of AlSb. The pseudopotential form factors were determined by fitting to reliably assigned optical transition energies. Optical critical points and effective masses were evaluated and compared with experimental data so far as possible.This work was performed in the Arbeitsgemeinschaft A_IIIB_V-Halbleiter of the Karl-Marx University Leipzig. The authors are indebted to Dr. K.Unger for stimulating discussions.