变换光学是一种通过设计改变传输介质的电磁特性实现调控电磁波任意传输的理论。根据麦克斯韦方程组在空间变换下的协变性，可以通过坐标变换设计出具有特定电磁参数的材料，从而设计新型电磁器件满足对电磁波传输的特定需求。基于变换光学的方法，人们陆续提出了隐身斗篷，隐身地毯以及波束集中器等新型电磁功能器件。基于上述背景，应用变换光学的理论方法，本文提出并设计了一种可实现无反射传输的90°波导弯接头。对波导弯接头材料的电磁参数进行了重新设计，实现了对于入射波的传输方向的操控，满足无反射传输要求。然而，经过变换光学得到的波导接头材料电磁参数通常是各向异性的，因此在实际制备中很难实现。本文根据等效介质理论使用两种各向同性材料在特定方向上层叠等效实现了波导弯接头处各向异性材料的电磁特性。基于有限元方法，对设计的波导接头进行了数值仿真，结果表明：在填充了特定材料的弯曲波导接头处，电磁波可以实现无反射传播从而大幅提高了传输效率。

Transformation optics is a newly proposed theory which involves into a powerful tool set for the design of various novel electromagnetic devices that are difficult to conceive using regular methods.By taking advantage of the invariance of Maxwell Equations upon coordinate transformation,transformation optics yields a precise prescription of spatially-varying and anisotropic optical constant to guide wave propagation at our wills.It is well known that traditional waveguide bends in-herently suffer from reflections and mode distortions since a wave has to travel along paths of various lengths counting on the radial or cornered location inside the bends.To eliminate such vast reduction of transmission,we utilize the method of transformation optics to design a metamaterial placed in a 90 degree waveguide bend which can completely suppress the re-flections and modes perturbations to support perfect transmission.The constitutive parameters of the associated metamaterial in the wave

利用人工结构制成的超材料能够实现天然材料所不具备的特性,电磁超材料作为一个新兴、多学科交叉领域,在理论探究和实验证明上都已成为近年来科学研究的热点之一,除单负和双负材料之外,电磁参数近零的超材料因其在光学隐身、天线雷达、军事等方面的应用也受到科学家的广泛关注。本文利用共振的H分形结构设计制作了在微波频段下折射率分布在[0,1]之间的微波超材料,而且利用微波波导传输线对多种变化尺度的晶胞结构进行电磁参数的测量,得到了每种晶胞结构对应的X波段折射率频谱,通过研究晶胞结构单元的等效电磁参数实现了一种折射率近零超材料,从而为实现近零折射率分布的变换光学器件如Inside-out Eaton Lens的实验研制提供了材料选择。

Metamaterials made of artificial structures can realize exotic characteristics that natural materials do not possess. Electromagnetic metamaterials, a new and interdisciplinary field, have become one of the hottest topics both in theoretical exploration and experimental verification in recent years. Index-near-zero metamaterials have attracted scientists’ attention as well as single negative or double negative metamaterials because of their widely applications in optical cloaking , radar antenna and military stealth. In this paper, we design and fabricate a type of microwave metamaterials with effective refractive index ranging from 0 to 1, based on the H-fractal structures. We obtain the experimental refractive index spectra of the H-fractal metamaterials by measuring their transmissions and reflections in microwave waveguide transmission line, which proves the metamaterials with refractive index near zero. Our high-performance H-fractal metamaterials provide a designing platform for

电磁诱导透明现象因在慢光、光存储和非线性光学等领域的广泛应用,而成为当今科学研究的热点。因此利用人工电磁媒质实现的电磁诱导透明现象,即等离激元诱导透明,也引起了广泛的研究。文章论述了等离激元诱导透明的基本原理及研究现状,并重点分析了谐振子模型、电路模型以及耦合模理论三种等效模型,为进一步深入探究等离激元诱导透明提供了一定的理论研究基础。

Electronic induced Transparency has been applied in the field of slow light,the optic storage,and the nonlinear optics, thus recently PIT plays a more and more important role in the advanced scientific research.Therefore, the use of the metamaterials to achieve electromagnetically induced transparency, namely plasmon induced transparency, also caused extensive attention.In the paper,the fundamental and the recent research of the PIT have been discussed, simultaneously the Harmonic oscillator model, the equivalent circuit model and the coupled mode theory have been analysed, Which provide a theoretical basis for further research in plasmon induced transparency.

非接触测量方法以光电、电磁、超声波等技术为基础,在仪器的感受元件不与被测物体表面接触的情况下,即可获取被测物体的各种外表或内在的数据特征。详细阐述了部分常用的光学法和非光学法测量技术及相应的测量仪器,说明了这些非接触测量方法的原理、优缺点、精度及适用范围,指出了未来非接触测量技术的发展趋势。

Non-contact measurement method is based on photoelectric,electromagnetic,ultrasonic technology and so on.In the case of feelings element of the instrument is not in contact with the surface of the measured object,a variety of appearance or the intrin-sic characteristics of the data of the measured object can be obtained.Some of the commonly used optical and non-optical measurement methods and corresponding measurement instruments were illustrated in detail.The principle,advantages and disadvantages,precision and applying scope of non-contact measurement methods were introduced.The future development trend of the non-contact measure-ment technology was proposed.

基于光学变换理论,提出了一种新型的具有旋转和放大功能的光学变换器件,该器件可由具有正折射率参数的超常媒质实现。推导了所提出的器件材料的本构参数张量的通解表达式,并采用全波电磁仿真软件进行了仿真验证。仿真结果证实了所导出的本构参数张量的正确性,即该器件可以起到使置于内部的物体旋转和放大的效果。因此,所提出的器件将在电磁场工程等领域有潜在的应用。

Based on theory of optical transformation, a novel rotatable and amplifying optical transformation device was proposed, and this device could be realized with metamaterials with parameters of positive refraction index. The constitutive tensors of the proposed device were derived, and then some full wave simulations of the devices based on the above constitutive tensor were performed to confirm the functionality of the proposed device. The simulations results verified that the proposed device can make the inside object rotate and enlarge. Therefore, it is expected that the proposed device will have potential applications in the electromagnetic engineering.