晶体球法直接测量KTP晶体第Ⅰ类相位匹配曲线

报道了35ps激光脉冲射入直径为10mm KTP昌体球的第Ⅰ类相位匹配二次谐波产生实验,根据二次谐波产生转换效率直接测量了KTP晶体的第Ⅰ类相位匹配曲线及相应的有效非线性系数,并与6组色散方程给出的理论匹配曲线比较,指出Vanherzele的公式优于其他五组。     

SUSY—QCD Corrections to B^0—B^0 Mixing

We study the SUSY-QCD corrections to B^0-B^0 mixing with a reasonable SUSY parameter space and find that contribution from gluio is proportional to log(mg/μω) where μω is the weak interaction energy scale and by no means negligible.     

The Effective AC Response of Nonlinear Composites

A perturbative approach is used to study the AC response of nonlinear compostie media,which obey a current-field relation of the form J=σE χ|E|^2E with comp[onents having nonlinear response at finite frequencies.For a sinusoidal applied field,we extend the local potential in terms of sinusoidal components at fundamental frequency and high-order harmonic frequencies to treat the nonlinear comosites.For nonlinear composite media with a low concentrations of spherical inclusions,we give the formulae of the nonlinear effective AC susceptibility χ3ω at the third harmonic frequency.     

QCD One-Loop Effective Coupling Constant and Quark Mass Given in a Mass-Dependent Renormalization

The QCD one-loop renormalization is restudied in a mass-dependent subtraction scheme in which the quark mass is not set to vanish and the renormalization point is chosen to be an arbitrary time-like momentum. The correctness of the subtraction is ensured by the Ward identities which are respected in all the processes of subtraction.By considering the mass effect, the effective coupling constant and the effective quark masses derived by solving the renormalization group equations are given in improved expressions which are different from the previous results.     

QCD One-Loop Effective Coupling Constant and Quark Mass Given in a Mass-Dependent Renormalization

The QCD one-loop renormalization is restudied in a mass-dependent subtraction scheme in which the quark mass is not set to vanish and the renormalization point is chosen to be an arbitrary time-like momentum. The correctness of the subtraction is ensured by the Ward identities which are respected in all the processes of subtraction.By considering the mass effect, the effective coupling constant and the effective quark masses derived by solving the renormalization group equations are given in improved expressions which are different from the previous results.PACS numbers: 11.10.Gh, 11.10.Hi, 12.38.-t, 12.38.Bx     

Dynamical Properties of a Single-Mode Laser with Both Colored Noise and Injected Signal

The colored noise in a single-mode laser with injected signal is investigated by the method of two-dimensional unified colored noise approximation. The normalized correlation function λ₂(0), the intensity correlation time T_c and effective eigenvalue λ_eff are calculated. The effects of the injected signal I₀, colored noise strength P^ˊ and the noise correlation time τ on the dynamical properties of the single-mode laser are discussed.     

PERIODIC SOLUTIONS OF DELAY DIFFERENTIAL EQUATIONS WITH TWO DELAY VIA BI-HAMILTONIAN SYSTEMS

1 Illtroduction and Statement of the Main ResultIn this paper, we shall study the existence of periodic solutions for the twofOllowing differential delay equationsX'(t) = --f(x(t -- r1))g(x(t -- r2)) -- f(x(t -- r2))g(x(t -- r1)), (1)andX'(t) = f(x(t -- rl))g(x(t -- r2)) f(x(t -- r2))g(x(t -- rl)), (2)where ri (i = l,2) are positive constants. When the function g(x) = 1,equations (1) and (2) become respectivelyIn 1974, Kaplan and Yorke (see [101) proved the existence of periodic so1utions…     

Geometric properties of QCD string from Willmore functional

The extremum of the Willmore-like functional for m-dimensional Riemannian manifold immersed in d-dimensional Riemannian manifold under normal variations is studied and various cases of interest are examined. This study is used to relate the parameters of QCD string action, including the Polyakov–Kleinert extrinsic curvature action, with the geometric properties of the world sheet. The world sheet has been shown to have negative stiffness on the basis of the geometric considerations.     

大尺寸团簇在超短超强激光场中的动力学行为

利用“流体动力学”模型分析了超短脉冲激光与团簇的相互作用机制.在共振吸收附近,等离子体球的电子密度、温度由于共振吸收加热和团簇膨胀变化非常快,仅用准静态的介电常数并不能完全描述团族在共振吸收处的物理过程.提出了有效介电常数模型,对团簇在共振吸收处的行为进行了适当的修正,并且分析了高价电离态离子和高能离子产生的机制以及不同波长激光和团簇尺寸对高价电离态离子和高能离子产生机制的影响 关键词： 超短超强激光 团簇 共振吸收 有效介电常数     

液氦薄膜表面上与涟波子耦合的电子的有效质量

研究在液氦薄膜表面上与涟波子（ripplon)相互作用的二维电子的性质。采用线性组合算符和拉格郎日乘子法,导出了强、弱耦合两种极限情况下二维电子的有效质量。