太赫兹金属线波导耦合模理论研究(英文)

基于耦合模假设,研究了描述两太赫兹金属线波导之间耦合特性的耦合模理论.通过采用与光波导耦合模理论等价的近似,研究得到了耦合方程和耦合系数表达式.进而,研究得到了两个相同金属线波导的耦合方程解及耦合特性.所提出的理论对于描述两金属线波导之间的能量传递具有重要的意义.     

Simulation of the Propagation Property of Metal Wires Terahertz Waveguides

The propagation property of metal wires terahertz waveguides is studied and simulated under the framework of the Sommerfeld model. The group velocity dispersion, attenuation amplitude, transverse magnetic mode and propagating energy have been obtained by numerically solving the complex eigenvalue equation for the propagation constant. It is found that the group velocity dispersion and attenuation amplitude decrease with the increasing radii of metal wires. The energy power within the dielectric layer increase with the increase of radiation frequency.     

A New Method to Analyse Two-Side Tapered Waveguides

We discuss the characters of two-side tapered waveguides. Then, based on some approximations, a simple but practical and efficient method is developed to design the taper waveguide. The results are compared with other methods in a good agreement.     

确定介质波导导模折射率的一种新方法

介绍一种确定平面介质波导导模折射率的新法，它是Ｒｕｓｃｈｉｎ－Ｌｉｔ计模法的推广，与计模法有关的半相位移关系得到完善，本文还给出新法在几种有代表性波导中的应用和计算结果。     

Experimental Investigation on Terahertz Spectra of Amphetamine Type Stimulants

The spectral absorption features of three amphetamine-type stimulants （ATS） belonging to illicit drugs have been studied with terahertz （THz） time-domain spectroscopy （THz-TDS） and the characteristic absorption spectra （fingerprint spectra） are obtained in the range from 0.2 to 2.5 THz. Fingerprint spectra of illicit drugs in terahertz band are bases to detect and to inspect nondestructively illicit drugs with terahertz technique. With fingerprint spectra of illicit drugs and strong penetrability for cloths, paper bags and leathered or plastic luggage terahertz technique would be better than other techniques in illicit drugs detection and inspection. Thus, this work would contribute to the building of corresponding fingerprint spectra database of illicit drugs and provide experimental bases for using of terahertz detection apparatus in drugs nondestructive detection and inspection in the future.     

A New Theoretical Modeling of Surface Resistance in Normal Metals at Terahertz Frequencies

A number of researchers have reported discrepancies between surface resistance measurements and classical theoretical predictions for simple mm-wave and sub-mm-wave structures. We have developed a rigorous phenomenological model for analyzing surface resistance of normal metals. The model is based on quantum mechanical analysis for spatial dispersion within the metal. We have used the model to predict the surface resistance in normal metals at terahertz frequencies. Our analysis shows that the conductivity is not only frequency but also wave vector dependent. Moreover, we have compared the results of this model with the results of the classical skin-effect model and classical relaxation- effect model. We demonstrate that our model has good quantitative agreement with the published experimental data for the room temperature surface resistance of normal metals at terahertz frequencies range from the literature.     

克尔型介质平板波导中的弱非线性横向电场波

对芯子为克尔型非线性介质、覆盖层和衬底为线性介质的平板波导，在弱非线性近似下，导出了这类波导横向电场波满足的色散方程和场分布，其物理意义清晰，且大大降低了数值计算的强度。     

新型电光强度调制器的研究

在全硅和GeSi电光强度调制器研究的基础上，提出了一种新型的电光强度调制器结构，目的在于减小调制电流和提高调制频率。     

A New Type of Shape-Invariant Potential

It has been shown that Hulthen potental and isotonic harmonic oscillator potential are shape-invariant potentials with a translation of parameters, and isotonic harmonic oscillator potential and three-dimensional harmonic oscillator potential belong to a type of shape-invariant potentials.     

分析各向异性光波导的一种新系统

报道一种灵活，交互和自动化的系统，它以矢量有限无法为基础，并在ＩＭＳＬ的ＰＤＥ／ｐｒｏｔｒａｎ题解环境中实现，用它分析各向异性光波异，得到了各向异性介矩形导中所用传播模式的数值结果，以及采用传播常数和模场分布二种形式评价这个方法的精度，并与早期的研究结果加以比较。     

A Review of IR Transmitting,Hollow Waveguides

Abstract

An analysis and experimental data of the time-dependent response of an all-fiber ring resonator in which the ring is illuminated by a phase modulated input beam are presented. The resonator is operated as a high-resolution optical-scanning spectrometer. Since the resolution limit is a function of the finesse and cavity-loop length, we will show that it is not possible to design a high-resolution ring resonator that will not produce a distorted output signal when the phase modulation rate is comparable to the response time of the ring.     

高速视频硬盘记录系统分析

为了提高视频记录速度,通过分析视频记录系统的数据通道,找出通道的瓶颈所在;通过研究文件大小与存储速度的关系,采用RAID 0技术和文件合成与分割技术提高硬盘的存储速度,改善了系统的数据通道,最终达到了提高视频记录系统的整体速度,保证了记录数据的实时性和完整性.     

New Plasmon Waveguides Composed of Twin Metal Wedges with a Nano Gap

We have numerically shown the existence of coupled wedge plasmons (CWPs) which propagates along a nano gap of a twin metal wedge. The CWPs are formed by wedge plasmons which can interact with each other. The dispersion relations of the wavenumber, propagation distance, and beam area of CWPs, are described and show that the characteristics of CWPs are similar to those of wedge plasmons and of gap plasmons. We also propose a new plasmon waveguide composed of twin metal wedges with a nano gap.     

铌酸锂质子交换波导中切伦科夫倍频实验研究

报道了质子交换铌酸锂平板波导中切伦科夫倍频蓝绿光输出研究。理论上计算了质子交换波导参数对不同基波波长倍频转换效率的影响。制备出适合于蓝绿光输出的铌酸锂质子交换波导并观测到较高转换效率的倍频光产生,实验中我们测量了倍频转换效率与抽运动率以及抽运波长的关系,实验结果与理论预测吻合。     

亚波长之字形MIM等离子波导宽带滤波器

运用时域有限差分（FDTD）方法数值研究了一种亚波长之字形金属-绝缘体-金属（MIM）等离子波导结构的传输属性。之字形波导在连续两个拐角可向外延伸出1~4个短切口。每个切口独立构成一个谐振腔,谐振波长近似与切口深度成线性正比,而与切口方向无关。当任意一个切口满足谐振条件时,该波导结构在对应波长的透射率均趋近于0。随着同深度切口数目的增加,禁带波长区域逐渐展宽,形成一个良好的宽带滤波器。     

A Study of Wave Processes in Elastic Topographic Waveguides

Acoustical Physics - The characteristic features of acoustic wave propagation in orthotropic elastic topographic waveguides are investigated for waveguides in the form of extended cylindrical...     

一种新的菲涅耳位相波带片

利用液晶分子取向的电场可控及光学各向异性的特点,设计了一种新型的菲涅耳痊相波带片,这种器件具有制作简单、造价低廉、抗划损的优点。     

一种新型自感现象演示器——全国第五届自制教具评选获奖作之七

1传统自感现象演示器 目前广泛使用的自感现象演示器和现行高中物理教材都是分别用图1、图2所示两个电路演示和讲授通电和断电自感现象的,这种演示方法往往会使学生形成一个电路只出现一种自感现象的错觉,不能准确地表现客观事实.此外,这种仪器还存在如下缺点:     

A New Integrable Symplectic Map of Neumann Type

By resorting to the nonlinearization approach, a Neumann constraint associated with a discrete 3 × 3 matrix eigenvalue problem is considered. A new symplectic map of the Neumann type is obtained through nonlinearization of the discrete eigenvalue problem and its adjoint one. The generating function of integrals of motion is presented, by which the symplectic reap＇is further proved to be completely integrable in the Liouville sense.