基于GaAs的新型稀磁半导体材料(Ga,Mn)As

介绍了一种基于 Ga As的新型稀磁半导体材料 ( Ga,Mn) As,包括 ( Ga,Mn) As的制备方法、结构特性、磁性质及磁输运性质。最后 ,展望了 ( Ga,Mn) As的应用前景     

二元光学技术在激光成像雷达扫描器上的应用

激光扫描技术是在巡航导弹制导中应用的CO2激光成像雷达的关键技术之一.研制了圆盘型反射式位相计算全息光栅扫描器,扫描角度范围为10°×2°,分辨率为64点/行,衍射效率为27.6%.结合CO2激光成像雷达的特点及目前对二元光学技术理论和加工工艺的研究,提出:目前的二元光学技术,特别是多重掩模蚀刻工艺的发展,可使计算全息光栅扫描器成为解决CO2激光成像雷达扫描技术的有效途径.     

基于特征匹配的影像可匹配性研究

对基于特征匹配的影像可匹配性评价方法进行了探讨。从分析影像所包含的信息量入手,提出了通过计算影像的信息熵和累加梯度值进行基于特征匹配的影像可匹配性评价方法。通过基于角点特征和Hausdorff距离的影像匹配实验,发现影像信息熵和累加梯度值与影像可匹配性（即正确匹配概率）之间存在很强的相关性,尽管由于地表景观的不同,表现出的具体规律略有差异,但都表现出匹配正确率随影像信息熵和累加梯度的增大而增大的趋势。因此,可通过对影像信息量的评价来进行基准图的自动选取和飞行路径的规划;在实时匹配导航过程中,可根据获取的每一实时影像所含信息量,来决定是否进行匹配,这样既可以保证匹配的正确性,避免误导,又可节省匹配时间。提出方法对基于灰度相关的影像可匹配性评价具有借鉴意义。     

Creation of Ghost Illusions Using Wave Dynamics in Metamaterials

The creation of wave‐dynamic illusion functionality is of great interest to various scientific communities because it can potentially transform an actual perception into the pre‐controlled perception, thus empowering unprecedented applications in the advanced‐material science, camouflage, cloaking, optical and/or microwave cognition, and defense security. By using the space transformation theory and engineering capability of metamaterials, a functional “ghost” illusion device, which is capable of creating multiple virtual ghost images of the original object's position under the illumination of electromagnetic waves, is proposed and realized. The scattering signature of the object is thus ghosted and perceived as multiple ghost targets with different geometries and compositions. The ghost‐illusion material, which is being inhomogeneous and anisotropic, is realized using thousands of varying unit cells working at non‐resonance. The experimental demonstration of the ghost illusion validates the theory of scattering metamorphosis and opens a novel avenue to the wave‐dynamic illusion, cognitive deception, manipulate strange light (or matter) behaviors, and design novel optical and microwave devices.     

基于光纤的远程IO端口控制系统

介绍了一种基于光纤的远程IO端口控制系统,通过将光纤、以太网与嵌入式系统结合,采用VB6.0上位机软件实现远程通讯测试,提出了一种远程控制IO端口数据双向传输的解决方案。本系统以单片机MCF5223X系列芯片为主控模块的核心,从IO端口采集数据后由光纤传输至远端主机,远端主机通过VB6.0分析处理数据,使得远端主机与IO端口数据实时双向传输,实现远程控制IO端口的功能。本文给出了系统结构图和软件测试通讯图。     

Energetics of Donor‐Doping,Metal Vacancies,and Oxygen‐Loss in A‐Site Rare‐Earth‐Doped BaTiO3

The energetics of La‐doping in BaTiO₃ are reported for both (electronic) donor‐doping with the creation of Ti³⁺ cations and ionic doping with the creation of Ti vacancies. The experiments (for samples prepared in air) and simulations demonstrate that ionic doping is the preferred mechanism for all concentrations of La‐doping. The apparent disagreement with electrical conduction of these ionic doped samples is explained by subsequent oxygen‐loss, which leads to the creation of Ti³⁺ cations. Simulations show that oxygen‐loss is much more favorable in the ionic‐doped system than undoped BaTiO₃ due to the unique local structure created around the defect site. These findings resolve the so‐called “donor‐doping” anomaly in BaTiO₃ and explain the source of semiconductivity in positive temperature coefficient of resistance (PTCR) BaTiO₃ thermistors.     

An Efficient Multi-Path Self-Organizing Strategy in Internet of Things

In order to improve the organizing performance and fault tolerance of the wireless network protocol GEAR based on the geographical location information in the Internet of things and achieve better energy distribution and conservation effects. This paper proposes a new multipath routing organizing protocol (SMG, Self-organized Multipath GEAR) based on the basic geographic routing protocol GEAR. By two-step organizing, communication empty nodes and communication hole can join the network respectively and energy spreading out and mechanism of dormancy of the multi-path are utilized to spread out and save energy. Meanwhile, this paper presents an approximate estimation algorithm to estimate the number of the nodes in the monitoring region with a certain size and regular shape. The critical path node goes to failure in different times while received packet rate is monitored using the experiment of NS2 simulation and actual hardware. The experiment results show that the improved protocol increases the fault tolerance of the network, reduces the paralysis rate of the network and achieves the effect of energy spreading out and saving, increases the lifetime of the network through a multi-path strategy.     

光折变多量子阱的电吸收栅和电折变栅

在光折变多量子阱中，通过Ｆｒａｎｚ－Ｋｅｌｄｙｓｈ效应可写入电吸收栅和电折变栅。基于二波耦合理论，精确求解了由这两种光栅引起的光强耦合方程，近似计算了Ｒａｍａｎ－Ｎａｔｈ高阶衍射光强。     

角状螺旋固体激光器热畸变自补偿特性分析

利用张量方法对角状螺旋光路固体激光器作了分析，证实其在ｘ、ｙ两方向对激光介质的热畸变有自补偿作用，且ｘ、ｙ两方向呈对称性．