Up to 8-GHz Ultrafast Multi-Wavelength Routing Operation of Active Birefringent Fiber Loop Filter/Interleaver Using a Traveling-Wave-Type Phase Modulator

Ultrafast multi-wavelength routing by an active birefringent fiber loop filter/interleaver is proposed and demonstrated. In the proposed active filter, the loop part consists of a birefringent optical fiber and a traveling-wave-type phase modulator. Numerical simulation using Jones matrix analysis shows that the periodic transmission/reflection bands of the filter can be switched by changing a phase difference between clockwise and counter clockwise components passing through the birefringent fiber loop. Experimentally, we realize fast switching by controlling the applied voltage to the phase modulator, and 8-GHz wavelength routing operation is achieved.     

Jones Matrix Imaging of Biological Samples Using Parallel-Detecting Polarization-Sensitive Fourier Domain Optical Coherence Tomography

A polarization-sensitive Fourier domain optical coherence tomography (PS-FD-OCT) system has been developed. By using a two-dimensional CCD camera, this PS-FD-OCT simultaneously obtains two spectral interferograms corresponding to orthogonal polarization components of a probing beam. FD-OCT avoids axial mechanical scanning, therefore, two OCT images are obtained by a single lateral scanning. This system requires only two one-dimensional scannings for determining the Müller matrix images of a sample. In the Müller matrix images, the birefringence properties of the inner surface of a porcine esophagus are revealed.     

光学系统的偏振像差研究

综合论述了偏振像差的理论,给出了具体的例子,指出偏振是影响光学系统性能的一个重要因素,要想提高光学系统的性能,必须控制光学系统的偏振像差,而且光学系统设计必须与光学薄膜的设计结合起来。     

On the relation between the A-polynomial and the Jones polynomial

This paper shows that the noncommutative generalization of the A-polynomial of a knot, defined using Kauffman bracket skein modules, together with finitely many colored Jones polynomials, determines the remaining colored Jones polynomials of the knot. It also shows that under certain conditions, satisfied for example by the unknot and the trefoil knot, the noncommutative generalization of the A-polynomial determines all colored Jones polynomials of the knot.

     

Parameterization of Ca+2-protein interactions for molecular dynamics simulations

Molecular dynamics simulations of Ca+2 ions near protein were performed with three force fields: GROMOS96, OPLS-AA, and CHARMM22. The simulations reveal major, force-field dependent, inconsistencies in the interaction between the Ca+2 ions with the protein. The variations are attributed to the nonbonded parameterizations of the Ca+2-carboxylates interactions. The simulations results were compared to experimental data, using the Ca+2-HCOO- equilibrium as a model. The OPLS-AA force field grossly overestimates the binding affinity of the Ca+2 ions to the carboxylate whereas the GROMOS96 and CHARMM22 force fields underestimate the stability of the complex. Optimization of the Lennard-Jones parameters for the Ca+2-carboxylate interactions were carried out, yielding new parameters which reproduce experimental data.     

On predicting self-diffusion coefficients in fluids

A modification of an existing correlative equation for self-diffusion coefficients is presented. A free-volume theory for liquids has been corrected to reproduce diffusivities of hard-sphere and Lennard–Jones fluids from low-density limit to melting points, and has been applied to correlate a wide database of non-polar, polar, quantic and hydrogen-bonding substances, although it is unable to fit helium, water and hydrogen fluoride. The adjustable parameters are generalized with available fluid properties, and the three resulting predictive formulas present lower deviations than other correlative equations used in a predictive way for non-quantic and non-associated fluids.     

Solvability,asymptotic analysis and regularity results for a mixed type interaction problem of acoustic waves and piezoelectric structures

In the paper, we investigate the mixed type transmission problem arising in the model of fluid–solid acoustic interaction when a piezoceramic elastic body (Ω⁺) is embedded in an unbounded fluid domain (Ω^?). The corresponding physical process is described by the boundary‐transmission problem for second‐order partial differential equations. In particular, in the bounded domain Ω⁺, we have a 4×4 dimensional matrix strongly elliptic second‐order partial differential equation, while in the unbounded complement domain Ω^?, we have a scalar Helmholtz equation describing acoustic wave propagation. The physical kinematic and dynamic relations mathematically are described by appropriate boundary and transmission conditions. With the help of the potential method and theory of pseudodifferential equations based on the Wiener–Hopf factorization method, the uniqueness and existence theorems are proved in Sobolev–Slobodetskii spaces. We derive asymptotic expansion of solutions, and on the basis of asymptotic analysis, we establish optimal Hölder smoothness results for solutions. Copyright © 2017 John Wiley & Sons, Ltd.     

用琼斯算法求解椭圆光正反射问题需采用的数学处理方法

采用琼斯算法并结合Poincare球的图示研究了单色椭圆偏振光经理想平面镜正反射的特性,然后将获得的结论推广到圆偏振光及线偏振光经平面镜正反射的情形,再用偏振态几何参量表示法对结论加以验证,并提出便于记住结论的镜像法,以期对椭圆偏振光正反射问题的琼斯算法及获得结果的物理含义给出比较直观的诠释。同时指出采用琼斯算法求解偏振光学问题时需采用的特殊数学处理方法及产生这一现象的原因。     

光学玻璃应力双折射叠加

为解决在光学玻璃应力双折射测量中遇到的双折射叠加问题,利用光学等效原理,使用一个线性双折射模型和一个旋转器来代替叠加模型。对叠加的情况做了分析和计算,得到了叠加后的特征延迟、主应力方向和旋转角随两个应力模型主应力方向夹角变化的曲线。理论分析表明,应力双折射叠加不是应力双折射的简单相加,而是与叠加模型各自的应力双折射值和主应力方向的夹角有关。实验结果与理论计算相吻合。应力双折射叠加对实际光学玻璃测试造成不良影响,使测量精度降低,特别是有透光支撑机构或折射液容器的情况下,应力双折射叠加的影响不可忽略。     

Jones多项式的一个赋值性质

Jones多项式的赋值性质反映了Jones多项式固有的本质.考虑了链环的Jones多项式的2阶导数在t=1时的值,利用已有的一些赋值公式以及Jones多项式和Conway多项式系数的一些性质,给出了它的一个计算公式.