Quantum correlations of helicity entangled states in non-inertial frames beyond single mode approximation

A helicity entangled tripartite state is considered in which the degree of entanglement is preserved in non-inertial frames. It is shown that Quantum Entanglement remains observer independent. As another measure of quantum correlation, Quantum Discord has been investigated. It is explicitly shown that acceleration has no effect on the degree of quantum correlation for the bipartite and tripartite helicity entangled states. Geometric Quantum Discord as a Hilbert–Schmidt distance is computed for helicity entangled states. It is shown that living in non-inertial frames does not make any influence on this distance, either. In addition, the analysis has been extended beyond single mode approximation to show that acceleration does not have any impact on the quantum features in the limit beyond the single mode. As an interesting result, while the density matrix depends on the right and left Unruh modes, the Negativity as a measure of Quantum Entanglement remains constant. Also, Quantum Discord does not change beyond single mode approximation.     

Evaluation of single virus detection through optical biosensor based on microsphere resonator

Shift of resonance frequency in microsphere optical resonator due to attachment of a desirable particle is obtained. Our 3-D finite element numerical method (FEM) simulations’ results show the path of light through microsphere and its variation due to attachment of particle. It is apparent that after attachment of particle to microsphere's surface, light is inclined to pass through the particle. Subsequently, the path of light becomes longer than previous. Because of this phenomenon, the resonance wavelength shifts to longer wavelengths. It is shown that microsphere optical resonator is a prominent biosensor for single virus detection since we applied characteristics of virus for particle in our simulations. Response of this biosensor depends on the characteristics of particle like its radius as we show in this article. Transmission spectrum of fiber which reveals a selected resonance frequency, have been studied in the frequency range of 106.3 to 107 THz under three different sizes of particles. The results show that the amount of frequency shift rises by enhancement of particle's size.     

Current-mode current-tunable four-phase quadrature oscillator

A current-mode current-tunable four-phase quadrature oscillator (QO) using current differencing transconductance amplifiers (CDTA) is presented in this paper. The proposed QO consists of three CDTAs and two grounded capacitors, which can provide four quadrature current outputs at high impedance nodes. The proposed QO has the advantages of electronically and independently control of oscillation condition and oscillation frequency. Moreover, the active and passive sensitivities of the QO are low. Cadence IC Design Tools 5.1.41 post-layout simulation results are included to confirm the theory.     

Large mode area OmniGuide fiber with superconductor-dielectric periodic multilayers cladding

An OmniGuide fiber consisting of superconductor–dielectric cladding periodic multilayers is investigated. The theoretical results of the OmniGuide fiber are presented and compared with that of multicore photonic crystal fiber and step-index fiber. The large mode area and low loss with small bending radius are observed by the OmniGuide fiber.     

Optimization the coupling coefficient of large mode area PCF using 2D FDTD method

The 2D FDTD method is used to design a tapered photonic crystal fiber, where large mode area is prominently coupled to optical fiber. For the first time, we observed that the mode area is stabilized with respect to possible fabrication tolerance by implementing a secondary surrounding waveguide with configuration of large air holes in the outer ring. The mode field area can be obtained in tapered region using a full vectorial H field technique. Beside these, the coupling coefficient can be optimizing by using least square boundary residual technique.     

调制状态下目标超分辨成像研究

给出了一种调制状态下目标的超分辨逆合成孔径雷达成像方法,不仅解决了调制等因素对目标成像的影响,而且还提高了对目标的二维分辨能力.首先,利用复数经验模态分解算法将雷达回波分解,并弃除影响成像的调制成份,同时重构目标刚体回波;其次,利用回归模型和Burg算法对目标回波建模和估计;再次,基于估计的回归模型,对刚体回波的距离向和方位向外推来提高对目标的二维分辨能力;最后,利用经典的距离多普勒算法对目标稳健成像.基于仿真和实测数据,给出了文中方法与其他方法的成像结果.     

超声扫描显微镜的厚度测量方法

基于超声扫描显微镜,在基本的反射扫描方式基础上开发出厚度测量扫描方式。作为实验室中的无损测厚工具,可以精确测量器件或器件中某材料层的厚度。     

中国与东南亚水资源合作开发模式分析

本文首先研究目前我国与东南亚国家水电项目合作开发所采用的两种主要的投资模式,分析比较两种投资模式的异同,最后提出意见和建议。     

采用计算机技术分析不同训练者跳深时的运动学特征

超等长训练作为提高爆发力最有效的方法致之一,尤其是下肢超等长练习-跳深,由于其独特的肌肉工作机制及练习手段,成为提高下肢快速肌肉力量最有效的方法之一。本研究重点使用高速摄影机和三维测力台对两组受试者在四个高度跳深练习中各个阶段所表现出的运动学特征进行测试,得出如下结论两组受试者各高度跳深中,最大缓冲膝关节角度根据受试者的不同表现为与之相适应的特点;完成各高度跳深时无训练经历者下肢髋、踝关节缓冲幅度显著增大,通过相关计算,说明有训练经历者下肢踝关节支撑退让能力大于普通人群。     

高功率1分32路功率分配网络的设计

为满足高功率微波辐射天线对其馈电系统的要求,提出了一种新型的高功率1分32路功率分配网络.该功率分配网络由同轴波导到两路矩形波导、H-T分支和波导同轴转换器三个元件构成,其32路输出具有等幅同相的功率分配特性.该分配网络的中心频率为2.88 GHz,对其结构进行了仿真优化设计和测试.结果表明:该功率分配网络在中心频率2.88 GHz处驻波比为1.13,对应的转换效率为98.8％,功率容量2.3 GW;在2.85～2.91 GHz内驻波比小于1.2,对应的转换效率大于97.8％.