一种新型的两态叠加多模Schrdinger猫态光场的等阶N次方Y压缩

本文根据量子力学的线性叠加原理,构造了由多模（即q模时目平态的相反态|｛｛－Zj｝〉q及多模虚相干态|｛｛－Zj｝〉q这两者的线性叠加所组成的一种新型的多模Schrodinger猫态光场利用新近建立的多模压缩态理论,研究了态的N次方Y压缩效应,结果发现：①当压缩阶数N＝Zp且p＝2m（m＝1,2,3,…,…）时,态。总是恒处于N－Y最小测不准态;②当压缩阶数N＝2p且p＝2m＋1（m＝0,1,2,3,…,…）时,如果各模的初始相位,态间的初始相位差以及各单模相干态光场的平均光子数之总和等满足一定的量子化条件,则态可呈现出周期性变化的、任意阶的N次方Y压缩效应;③当压缩阶数N＝2P＇＋1时,无论p＇＝2m（m＝0,1,2,…,…）还是p＇＝2m＋1（m＝0,1,2,3,…,……）,只要各模的初始相位满足一定的量子条件,则当两态叠加几率幅满足时,态就恒处于N－Y测不准态,始终不呈现N－Y最小测不准态和N次方Y压缩;而当时,态始终不呈现N－Y测不准态、N－Y最小测不准态和N次方Y压缩效应．     

Rarefied Flow Computations Using Nonlinear Model Boltzmann Equations

High resolution finite difference schemes for solving the nonlinear model Boltzmann equations are presented for the computations of rarefied gas flows. The discrete ordinate method is first applied to remove the velocity space dependency of the distribution function which renders the model Boltzmann equation in phase space to a set of hyperbolic conservation laws with source terms in physical space. Then a high order essentially nonoscillatory method due to Harten et al. (J. Comput. Phys. 71, 231, 1987) is adapted and extended to solve them. Explicit methods using operator splitting and implicit methods using the lower-upper factorization are described to treat multidimensional problems. The methods are tested for both steady and unsteady rarefied gas flows to illustrate its potential use. The computed results using model Boltzmann equations are found to compare well both with those using the direct simulation Monte Carlo results in the transitional regime flows and those with the continuum Navier-Stokes calculations in near continuum regime flows.     

Si1-xCex/Si量子阱发光材料制备及特性研究

在si(100)衬底上用分子束外延成功生长了Si_(1-x)Ge_x/si量子阱发光材料,发现在生长过程中背景杂质含量直接影响材料的发光特性,用光致发光(PL)和卢瑟福背散射(RBS)对样品质量进行标定。在PL测量中观察到合金量子阱带边激子分辨峰,并对发光峰能和峰宽作了讨论。 关键词：     

洛伦兹规范条件下对单胶子夸克势的QCD非微扰修正形式

在洛伦兹规范条件下,导出了具有平移不变性的双胶子两点函数真空平均值.利用所获得的双胶子真空期待值,给出了对微扰单胶子交换夸克–夸克势、夸克–反夸克对湮没和夸克–反夸克对激发势的最低阶非微扰QCD修正形式.     

衍射光学元件衍射效率影响混合光学系统性能的一种分析方法

本文从衍射光学元件的衍射效率入手,详细地分析了衍射光学元件衍射效率同混合光学系统光学传递函数的关系,并通过一个实际例子对所分析的结果进行了深入讨论.     

多模复共轭虚偶相干态光场的等阶N次方Y压缩与等阶N次方H压缩

本文利用新近建立的多模压缩态理论,详细研究了一种新型的多模复共轭虚偶相干态光场|Ψ_i,e^*(2)>_q的广义非线性等阶N次方Y压缩与等阶N次方H压缩特性.结果发现:1)当压缩阶数N为奇数时,态Ψ_i,e^*(2)>_q在一定条件下总可呈现出周期性变化的、任意阶的等阶N次方Y压缩效应;当腔模总数q与压缩阶数N两者之乘积q·N为奇数时,则在一定条件下态|Ψ_i,e^*(2)>_q又可呈现出周期性变化的、任意阶的等阶N次方H压缩效应.2)态|Ψ_i,e^*(2)>_q与多模偶相干态光场|Ψ_i,e^*(2)>_q与多模虚偶相干态光场|Ψ_i,e⁽²⁾>_q的压缩幅度、压缩条件和压缩特征等完全相同.这一结果再次从理论上证实了多模压缩光中的确存在着“相反压缩”和“压缩简并”这两类新的物理现象.     

氮烃混合工质中氖的作用机理

氮烃混合工质由于有较大的制冷量,在节流制冷器中已广泛应用,然而它的制冷温度却较高,在使用中受到一定的限制。文中通过对在氮烃混合工质中加入氖的分析,揭示了氖降低混合工质制冷温度的机理     

一些集的基数(Ⅷ)

Let X be an infinite set, C={B:B is a Boolean algebra defined on the X},Define B={D:D is isomorphie to B}, C={C & B is atomic},C_2= {C & B is not atomic},then |C_1|=|C_2|=2~(|x|). The power set of X is denoted by P(X), P(X) is a field of sets (Under Union and Intersection of sets, and Complement of set), Suppose K={F:F js a field of sets & FP(X)}, K_1={K},K_2{K & F is not atomie} then |K_1|=|K_2|=2~(2~(|x|)).     

Influence of Hydrothermal Temperature on Structures and Photovoltaic Properties of SnO2 Nanoparticles

Two SnO₂ nanoparticles were synthesized by hydrothermal method at 170°C and 180°C, respectively. Transmission electron microscope observations reveal that the diameters of both the nanoparticles are around 6nm. At the same time, surface photovoltage spectroscopy measurements show that the nanoparticle synthesized at 180°C has more surface electronic states at 0.3eV below the conduction band than the one synthesized at 170°C. This means that the temperatures chosen in hydrothermal synthesis have significant influence on the surface electronic characteristics of resultant SnO² nanoparticles but the effect on their sizes is not obvious. However, after being calcined at 500°C for 2h, the diameter of the nanoparticle synthesized at 180°C increased to 23nm and that of the nanoparticle synthesized at 170°C increased to 32nm as calculated from X-ray diffraction pattern.     

Analysis of High Power Millimeter Wave Waveguide Mode Converters with Input Mode Mixture

Based on the coupled mode theory, this paper presents the study on the influence of input mode mixture in circular oversized waveguide mode converters. Three kinds of commonly used waveguide mode converters, including the waveguide mode converters with varying wall radius or small axis perturbations, and the waveguide mode converters with bent structures, are taken as the examples. The results show that the spurious input modes do not simply superimpose onto the output modes, and in some cases they may deteriorate the conversion efficiency for the main output mode. Methods for transforming such spurious input mode mixture simultaneously into the main output mode are also presented in this paper.