Fermilab top mass and modified Fritzsch mass matrices

Fritzsch like mass matrices with non-zero 22-elements both in U sector and D sector have been investigated in the context of latest data regardingm _t ^phys , |V _ub|, |V _cb|, |V _td| and |V _ts|. Unlike several other phenomenological models, the present model not only accommodates the value ofm _t ^phys in the range 150–240 GeV, encompassing the CDF and D0 values, but is also able to reproduce |V _cb| ≊0.040 and |V _ub/V_cb| = 0.08±0.02 and |V _td| is predicted to lie in the range 0.005–0.014. Further, the angles of the unitarity triangle, related to the CP-violating asymmetries, are calculated to be in the ranges −1.0⩽sin2α⩽−0.1, 0.6 ⩽sin2α⩽1.0 and 0.48⩽sin2β⩽0.56, which are in agreement with other recent calculations.     

<Emphasis Type="Italic">In situ</Emphasis> X-ray diffraction study of structural evaluation in Fe<Subscript>73</Subscript>Cu<Subscript>1.5</Subscript>Nd<Subscript>3</Subscript>Si<Subscript>13.5</Subscript>B<Subscript>9</Subscript> amorphous alloy at high temperature

The thermodynamics structural relaxation of Fe₇₃Cu_1.5Nd₃Si_13.5B₉ amorphous alloy from room temperature to 400°C has been investigated by measuring the structure factor with in situ X-ray diffraction. The structural information of the atomic configuration such as radial distribution function (RDF) and neighbor atomic distance was gained by Fourier transformation. The research result shows that the amorphous structure remains stable in the temperature range of 30 to 400°C but exhibits distinct changes in local atomic configuration with the increase of temperature. The quantitative determination of the neighbor atomic distance suggests that the degree of short-range order changes by the temperature altering the second nearest neighbor local atomic configuration of the amorphous when structural relaxation occurs. Supported by the Natural Science Foundation of Hebei Province of China (Grant No. A2007000296), the National Natural Science Foundation of China (Grant No. 50731005), SKPBRC (Grant Nos. 2007CB616915 and 2006CB605201), and PCSIRT (Grant No. IRT0650)     

多模虚共轭相干态与多模真空态组成的叠加态光场的等阶N次方H压缩

构造了由多模虚共轭相干态|{iZ_j^*}〉_q与多模真空态|{0_j}〉_q两者的线性叠加所组成的两态叠加多模叠加态光场|{Ψ_q⁽²⁾}〉_q.利用多模压缩态理论,首次对该态的等阶N次方H压缩特性进行了详细研究.结果发现:态|{Ψ_q⁽²⁾}〉_q是一种典型的多模非经典光场,它可呈现出周期性变化的、任意阶的等阶N次方H压缩效应.     

Classical spin liquid properties of the infinite-component spin vector model on a fully frustrated two dimensional lattice

Thermodynamic quantities and correlation functions (CFs) of the classical antiferromagnet on the checkerboard lattice are studied for the exactly solvable infinite-component spin-vector model, D↦∞. In contrast to conventional two-dimensional magnets with continuous symmetry showing extended short-range order at distances smaller than the correlation length, r ξ _c∝ exp(T ^*/T), correlations in the checkerboard-lattice model decay already at the scale of the lattice spacing due to the strong degeneracy of the ground state characterized by a macroscopic number of strongly fluctuating local degrees of freedom. At low temperatures, spin CFs decay as < >∝ 1/r ² in the range a ₀≪r≪ξ _c∝T ^-1/2, where a₀ is the lattice spacing. Analytical results for the principal thermodynamic quantities in our model are very similar with MC simulations, exact and analytical results for the classical Heisenberg model (D = 3) on the pyrochlore lattice. This shows that the ground state of the infinite-component spin vector model on the checkerboard lattice is a classical spin liquid. Received 16 November 2001 and Received in final form 12 February 2002     

Charged pion condensation in anti-parallel electromagnetic fields and nonzero isospin density

The formation of charged pion condensate in anti-parallel electromagnetic fields and in the presence of the isospin chemical potential is studied in the two-flavor Nambu-Jona-Lasinio model.The method of Schwinger proper time is extended to explore the quantities in the off-diagonal flavor space,i.e.the charged pion.In this framework,π^± are treated as bound states of quarks and not as point-like charged particles.The isospin chemical potential plays the role of a trigger for charged pion condensation.We obtain the associated effective potential as a function of the strength of the electromagnetic fields and find that it contains a sextic term which possibly induces a weak first order phase transition.The dependence of pion condensation on model parameters is investigated.     

On the Nano/Micro-Mechanics of Metallic Glass

Metallic glass (MG) is amorphous and has some outstanding properties such as ultrahigh strength, superior elasticity, and excellent thermo-plasticity. However, as MG is relatively new to the metal family, the relationship between its physical properties and amorphous structure is still unclear. This article aims to provide an insightful discussion through a comprehensive review about the investigations in the past few decades on the scientific mechanisms of this class of material. The discussion of the paper will include the following key aspects: (1) the formation mechanism of an amorphous structure through glass transition, (2) the structural characterization and models, (3) the micromechanics of plastic event and shear band, and (4) the correlation between the amorphous structure and its mechanical properties.     

二元高阶Lipschitz函数类和二重Fourier级数

利用二元函数的(r,s)阶差分和二元连续模函数定义了二元周期函数的高阶Lipschitz函数类Λr,s(ω)和λr,s(ω),并且从函数Fourier级数的系数出发,在复数域内给出了函数属于二元周期函数类的充分条件,在实数域内给出了函数属于二元周期函数类的充要条件.     

三阶色散影响下二阶孤子间互作用及抑制

在色散位移光纤中，研究了三阶色散影响下同相和反相二阶孤子之间的互作用，分析了同相和反相二阶孤子对衰变后时域波形和频域频移的变化，发现三阶色散使二阶孤子分裂出一大一小两个不同振幅的基阶孤子，并彼此分离，但孤子对中心频率频移量却减小。通过采用非线性增益控制的方法可以有效抑制二阶孤子间的互作用，使孤子保型传输而不发生衰变。同时通过周期性改变三阶色散系数，可以减小三阶色散的不利影响，抑制孤子中心频率的频移，使孤子对不偏离原来时间槽，稳定孤子传输。     

高次非球面的工艺技术研究

 高次非球面在光学系统应用中意义重大,但是一直以来缺乏一套快速、有效的工艺方法。利用VC6.0编制了一款面型计算软件以辅助加工,并提出了一种新的高次非球面补偿检验方法。针对一块巡天光谱仪中口径Φ244 mm的一面平面另一面为高次非球面的改正镜开展工艺方法的设计与研究,从铣磨成形开始,根据高次非球面的特点提出了几种新型磨削工艺,建立相应的数学模型。由于高次非球面的特殊性,试验了数控铣磨直接成型法,很大程度上降低后继工艺难度,在细磨和抛光阶段采用数控小工具和整工具研磨相结合,能够很好地克服面型不平滑等技术难题。总结出了一套高效率、低成本、高精度的高次非球面工艺方法。