An inequality connecting entropy distance,Fisher Information and large deviations

In this paper we introduce a new generalisation of the relative Fisher Information for Markov jump processes on a finite or countable state space, and prove an inequality which connects this object with the relative entropy and a large deviation rate functional. In addition to possessing various favourable properties, we show that this generalised Fisher Information converges to the classical Fisher Information in an appropriate limit. We then use this generalised Fisher Information and the aforementioned inequality to qualitatively study coarse-graining problems for jump processes on discrete spaces.     

Propagation of the Hermite–Gaussian beams through misaligned optical system with a circular aperture

By means of expanding a hard-edged aperture into a finite sum of complex Gaussian functions, the approximate analytical formula of one kind of higher-order Gaussian beams called the Hermite–Gaussian beams (HGBs) passing through circular apertured and misaligned optical system is obtained in this paper. The result provides more convenience for studying its propagation than the usual way by using diffraction integral directly. Some numerical simulations are also given for illustrating the propagation properties of the HGBs through the circular apertured optical systems.     

强流脉冲高斯分布束在磁四极透镜中的非线性传输

用李代数方法分析了高斯分布下强流脉冲束在磁四极透镜中的非线性传输.在高斯分布下,束流的空间电荷势可利用Green函数算出,进而可以得到包含束流自场的粒子运动的Hamilton函数.再施加李变换,就可以得到粒子运动的各级近似解.本文给出二级近似下的结果,根据需要,还可以扩展到更高级近似.计算过程需要进行迭代,即根据每次算出的轨迹值,确定束团在三维实空间中的大小,然后再进行迭代,直到满足精度要求为止.     

Large deviation for the empirical eigenvalue density of truncated Haar unitary matrices

Let U_m be an m×m Haar unitary matrix and U_[m,n] be its n×n truncation. In this paper the large deviation is proven for the empirical eigenvalue density of U_[m,n] as m/n→λ and n→∞. The rate function and the limit distribution are given explicitly. U_[m,n] is the random matrix model of quq, where u is a Haar unitary in a finite von Neumann algebra, q is a certain projection and they are free. The limit distribution coincides with the Brown measure of the operator quq.     

空间非相干多分量光束构成的非相干耦合屏蔽孤子对

两束本身具有空间非相干性的非相干多分量光束可以在光折变介质中形成非相干耦合 屏蔽孤子对，利用相干密度法得到了亮 亮、暗 暗型耦合孤子对的解，并研究了构成 非相干孤子对分量光束的相干组分的传播特性. 关键词： 空间非相干多分量光束 耦合孤子对 相干密度 相干组分     

空间电荷主导电子束的纵向聚焦设计

在空间电荷主导电子束研究中,纵向聚焦非常重要,在输运过程中由于强空间电荷力的影响,束团将很快变长并崩溃,马里兰大学的电子环设计用于方形束团和抛物线形束团的研究,环中需要用三个感应腔对束团进行纵向聚焦.文中首先介绍了方形束团和抛物线形束团的纵向束流动力学,推导了两种束团纵向聚焦所需要的5MHz重复率高压脉冲波形,并给出了实现纵向聚焦的感应腔设计及其特殊要求.     

大焦深成像系统仿真实验研究

如何增大非相干光学成像系统的焦深是应用光学研究领域的热点问题.本文对采用高次非球面光学掩模板与图像处理相结合增大成像光学系统焦深的新方法进行了深入分析,建立了大焦深成像系统仿真实验模型,并进行了大焦深成像系统仿真实验.实验结果证明了该方法在维持原相对孔径的同时使光学系统在较大的离焦范围内有好的成像质量.实际应用中还要综合考虑模板参量、信噪比等关键因素.     

强流束在二极磁铁中的非线性传输—Lie代数分析

 用Lie代数方法分析了带电粒子束在二极磁铁中的非线性传输，包含了空间电荷效应。粒子在相空间中的分布采用K V分布。轨迹分析的结果做到二级近似，根据需要，还可以扩展到三级或更高级近似。在分析中，将磁铁沿中心轨道分成若干小段。在每个小段上利用所得公式进行轨迹计算，得到自洽的解。然后重复此过程，作下一小段的计算，直到最后一个小段为止。     

Rotation of a Fine Particle with Circularly Polarized Anti-Parallel Collinear Laser Beams

We have succeeded in the operation of rotating a fine particle which was held without mechanical contact by circularly polarized laser beams with opposite propagation directions. A polystyrene latex particle 11.9 μm in diameter deformed in a disk-like shape was dispersed in water, and was trapped using the anti-parallel collinear laser beams which were set up so that they had the circular polarization rotating in the same direction. It was observed that the trapped particle rotated in the same direction as the rotation of the circular polarization of light. Inversion of the rotational direction of the circular polarization of light reversed the direction of the rotation of the particle. Although the rotational speed of a particle varied significantly from particle to particle, it was found to be proportional to the laser beam intensity. A typical value for the rotational speed per beam intensity was 2.1 Hz/W.