光子结构的猜想及其数学仿真

通过研究光的波粒二象性,对光子结构进行了研究并提出了自建光子模型.自建光子模型具有以下特性:①光子与原子核存在引力作用;②光子的电场与磁场交替变换使其具备了相位效应,且光强由光子数与光子相位和两个因素决定.在此基础上,通过借鉴天体物理中关于二体运动的三种轨迹,利用其中结论对大量原子核的引力作用进行概率分析,使用中心极限定理提出出射角度基本符合高斯分布的假设.接着对光子的相位叠加效应进行了分析.最后,对大量光子进行模拟仿真,并将仿真结果与单缝衍射、双缝干涉、多缝干涉现象等实验现象进行了对比.     

原子激光量子相干性的强光调控

在量子动力学的框架下,提出一种新的利用强入射光控制原子激光相干性的方法.与旋转波近似的情形不同,证明了：输出的原子激光束将会随时间演化而呈现一些非经典性质,如亚Poisson分布和正交分量的压缩效应.特别是,通过适当地调节初始射频（RF）场的相位,还可以实现输出稳定而更加明亮的压缩相干原子激光束.     

TW(1012W)飞秒激光作用下的超连续光谱的实验研究

利用飞秒脉冲啁啾放大系统所产生的TW级飞秒强光脉冲,以液体介质为研究对象,研究了不同介质长度(作用长度)、不同泵浦强度、介质的基频和倍频飞秒光脉冲的超连续光谱特性,在液体中实现了具有光谱“平台”效应的高转换率宽光谱,边缘光谱强度仅低于中心1个数量级,同时还研究了超连续谱形成过程中自相位调制(SPM)效应与四光子参量效应的作用。     

基于光子结构猜想的波动性现象建模仿真研究

综合龚祖同院士的光子类氢原子结构论和北大俎栋林教授的光子电磁场结构论,提出了两种结构相统一的理论猜想.基于猜想对单缝衍射、双缝干涉以及多缝干涉中光强与光子尺度、细缝宽度等参数的关系进行建模,并以双缝干涉为例进行了仿真实验.通过实验结果与经典波动光学中光强分布的对比,验证了模型的合理性.     

双光子共焦电子显微镜的三维成像理论及其分辨率的改善

研究了双光子共焦电子显微镜中双光子或多光子跃迁等非线性过程对成像特性的影响，导出了双光子共焦电子显微镜的荧光功率传输函数、三维脉冲响应函数和三维光学传递函数，进而导出了双光子荧光点像空间分布的理论表达式，并利用测不准原理阐明了双光子共焦电子显微镜如何突破经典衍射极限实现超分辨率三维成像.     

基于分形博弈的动量和反转效应转换研究

动量和反转效应普遍存在于证券市场,且会相互转换,但两者间相互转换的特征却鲜有人知.在多数派和少数派博弈的基础上,首次引入分形市场理论对投资者决策特征进行描述,据此建立了分形博弈过程,以分析动量和反转效应转换的统计特征.研究结果表明:在三种博弈机制下,分形博弈机制下的仿真收益率序列的统计分形特征更为接近实际序列的对数收益率序列,且动量和反转效应的相互转换与真实情况也异常相似,这体现了采用分形博弈分析动量和反转效应转换的有效性,为投资者构建有效的动量或反转投资策略提供了决策参考.     

中国股市跨行业动量效应和反转效应研究

动量效应和反转效应是两种重要的金融异象,质疑了有效市场假说。本文以2000～2009年的A股上市公司为研究样本,采用不同的形成期搭配不同的持有期下的投资策略考察了中国股市跨行业动量效应和反转效应。研究结论表明:在沪深A股市场,按下游行业收益率排序的零投资策略主要表现为动量效应,按上游行业收益率排序的零投资策略主要表现为反转效应。从短期来看,跨行业动量或反转效应普遍不显著。持有期中长时,结果的显著性明显提高。跨行业动量或反转效应通过CAPM、Fama-French、Carhart模型调整后仍然显著。     

饱和粘弹性土层中端承桩纵向振动的轴对称解析解

基于弹性和饱和多孔介质理论,将桩和饱和土层分别视为单相弹性介质和饱和粘弹性介质,利用Helmholtz分解和变量分离法,在频率域研究了饱和粘弹性土层中端承桩纵向振动的动力特性,给出了饱和粘弹性土层中桩纵向振动时动力响应的轴对称解析解及桩头复刚度的解析表达式．通过数值计算,给出了桩头动刚度因子和等效阻尼随激励频率的响应,考察了饱和土物性参数、桩土模量比、桩长径比、桩Poisson比等参数对桩头刚度因子和阻尼的影响．研究表明:由于考虑了桩的径向变形效应以及饱和粘弹性土层对桩的径向力作用,轴对称精确解的桩头动刚度因子和阻尼分别与经典Euler-Bernoulli杆模型桩的桩头动刚度因子和阻尼有较大的区别,特别是在若干激励频率处．因此,经典Euler-Bernoulli杆模型桩的适用性具有一定的局限,更加精确的分析应采用三维精确模型．     

基于光的波粒二象性猜想的数学仿真

从现有的经典物理光学理论和专业实验结果出发,运用数学思维,综合光子理论,建立了基于光的波粒二象性猜想的四种数学模型.针对光微子碰撞猜想,建立了基于光子碰撞后概率分布的模型.针对光子作为电磁场自我旋转的猜想,分别从专业证明和数学模型分析方面建立了电磁场偏转模型和光子旋转模型.最后建立了我们自己的猜想模型——光子蜂窝网络模型.该模型引入了"光子域"、"光子电力"、"光子磁力"、"光子键"等概念,从五个子模型出发,定性解释了四个光学现象,合理回答了题目提出的三大问题,并定量证明了衍射光强分布.     

基于分形市场理论的动量和反转效应转换研究

动量和反转效应广为人知,但两者之间会相互转换却鲜有人知.在少数派和多数派博弈的基础上,结合分形市场理论中投资者有限理性的特征,通过构建投资者的决策机制,建立了博弈过程,分析了动量和反转效应两者间的相互转换.研究结果表明,盈利动机驱使下,投资者在动量和反转策略集中选择成功率最高的策略进行实际投资,该种动态选择行为引致证券过度需求在正负之间转换,进而表现出动量和反转效应的相互转换.     

Quantum revivals of a non-Rabi type in a Jaynes–Cummings model

We study full revivals (e.g., the reappearance in the unitary evolution) of quantum states in the Jaynes–Cummings model with the rotating wave approximation. We prove that in the case of a zero detuning in subspaces generated by two adjacent pairs of energy levels, full revival does not exist for any values of the parameters. In contrast, the set of parameters that allows full revival is everywhere dense in the set of all parameters in the case of a nonzero detuning. The nature of these revivals differs from Rabi oscillations for a single pair of energy levels. In more complex subspaces, the presence of full revival reduces to particular cases of the tenth Hilbert problem for rational solutions of systems of nonlinear algebraic equations, which has no algorithmic solution in the general case. Non-Rabi revivals become partial revivals in the case where the rotating wave approximation is rejected.     

Numerical model for vibration damping resulting from the first-order phase transformations

A numerical model is constructed for modelling macroscale damping effects induced by the first-order martensite phase transformations in a shape memory alloy rod. The model is constructed on the basis of the modified Landau–Ginzburg theory that couples nonlinear mechanical and thermal fields. The free energy function for the model is constructed as a double well function at low temperature, such that the external energy can be absorbed during the phase transformation and converted into thermal form. The Chebyshev spectral methods are employed together with backward differentiation for the numerical analysis of the problem. Computational experiments performed for different vibration energies demonstrate the importance of taking into account damping effects induced by phase transformations.     

Application of the Jacobi functional equation and the ATS theorem in a quantum optical model

A new method is devised to study the atomic inversion in the model of a two-level atom interacting with a single quantized mode of the (initially coherent) electromagnetic field in an ideal resonant cavity. The method is based on number-theoretic results applied to the approximation of special series, specifically, on the functional equation for Jacobi theta functions and the ATS theorem. New asymptotic formulas are derived, with the help of which the behavior of the atomic inversion function on various time intervals can be determined in detail depending on the parameters of the system.     

Effect of atomic decay on purity,total correlations and entanglement of pure and mixed states

The atomic decay for a two level atom interacting with a single mode of electromagnetic field is considered. In particular for a coherent state or statistical mixture (SM) of two opposite coherent states as initial field states, the exact solution of the master equation is found. Effect of the atomic damping on the partial entropies of the atom or the field and the total entropy as a measures of the purity loss is investigated. The degree of entanglement by the negativity and the mutual information and the atomic coherence through the master equation is studied.     

谐和与有界噪声联合参激作用下的Visco-Elastic系统

研究了带visco-elastic项的非线性系统,在谐和与有界噪声联合参激作用下的响应和稳定性问题。用多尺度法分离了系统的快变项,并求出了系统的最大Liapunov指数和稳态概率密度函数,根据最大Liapunov指数可得系统解稳定的充分必要条件。讨论了系统的visco-elastic项对系统阻尼项和刚度项的贡献,给出了随机项和确定性参激强度等参数对系统响应影响的讨论。数值模拟表明该方法是有效的。     

Effects of Radiative Damping on Resonantly Generated Internal Gravity Waves

Internal gravity waves can propagate indefinitely upwards when a fluid is continuously stratified and unbounded vertically. This causes radiative damping of waves which are resonantly generated by the interaction between a mean flow and a topographic feature at the lower boundary. An evolution equation of Benjamin-Davis-Acrivos type, including temporal evolution, detuning, nonlinearity, dispersion, radiative damping, and forcing, is derived to describe the wave behavior. Using a pseudospectral method, we obtain and discuss various numerical results, especially for the resonant cases, covering forcing whose polarity is the same as, or opposite to, that of a free solitary wave, and for weak or strong radiative damping. In practice, weak-radiative cases are likely to be realized when an inversion layer exists at a certain low level over a mountain range.     

Statistical mechanical aspects of a spin- entropy system

In this paper we consider some statistical properties of the entropy due to the time development of a two-level system. Analytic expression for the density matrix is obtained to investigate the influence of the mean photon number on the atomic inversion, field and atomic Wehrl entropies. The results show that the general features of both entropies are similar.     

强阻尼波方程解的整体存在性和一致衰减性

这篇文章研究一类带非线性源项和非线性边界阻尼项的强阻尼波 方程强解和弱解的整体存在性和唯一性,进而也讨论解的一致衰减.     

Thermoelastic damping effect analysis in micro flexural resonator of atomic force microscopy

In the design of high-Q micro/nano-resonators, dissipation mechanisms may have damaging effects on the quality factor (Q). One of the major dissipation mechanisms is thermoelastic damping (TED) that needs an accurate consideration for prediction. Aim of this paper is to evaluate the effect of TED on the vibrations of thin beam resonators. In particular, we will focus on cantilever beam resonator used in atomic force microscopy (AFM). AFM resonator is actually a cantilever with a spring attached to its free end. The end spring is considered to capture the effect of surface stiffness between tip and sample surface. The coupled governing equations of motion of thin beam with consideration of TED effects are derived. In general, there are four elastic equations that are coupled with thermal conduction equation. Based on accurate assumptions, these equations are simplified and the various boundary conditions have been used in order to validate the computational procedure. In order to accurately determine TED effects, the coupled thermal conduction equation is solved for the temperature field by considering three-dimensional (3-D) heat conduction along the length, width and thickness of the beam. Weighted residual Galerkin technique is used to obtain frequency shift and the quality factor of the thin beam resonator. The obtained results for quality factor, frequency shift and sensitivity change due to thermo-elastic coupling are presented graphically. Furthermore, the effects of beam aspect ratio, stress-free temperature on the quality factor and the influence of the surface stiffness on the frequencies and modal sensitivity of the AFM cantilever with and without considering thermo-elastic damping effects are discussed.