阻抗匹配微波透镜

具有被动开关的时域超材料作为阻抗匹配吸收体

Temporal metamaterials with passive switching as impedance-matched absorbers

本文提出了一种具有被动开关的时域超材料，通过有效介质理论实现宽频带吸收，其性能超越Rozanov界限，并通过仿真验证了其作为一维完美匹配层的潜力。

理想阻抗匹配隔离器和单向吸收器

Perfect Impedance-Matched Isolators and Unidirectional Absorbers

提出了一种宽带无反射信道，它支持由回转元件和对称放置的增益和损耗元件之间的相互作用产生的单向波传播。主动元件的互换与回转反转一起将相同的结构转变为单向吸收器，其中来自特定方向的入射波被湮灭。当引入无序时，发现了非对称的安德森局域化，并讨论了在电子和光子电路框架下实现这种多功能结构的可能性。

Ultrathin 2 nm gold as ideal impedance-matched absorber for infrared light

Thermal detectors are a cornerstone of infrared (IR) and terahertz (THz) technology due to their broad spectral range. These detectors call for suitable broad spectral absorbers with minimalthermal mass. Often this is realized by plasmonic absorbers, which ensure a high absorptivity butonly for a narrow spectral band. Alternativly, a common approach is based on impedance-matching the sheet resistance of a thin metallic film to half the free-space impedance. Thereby, it is possible to achieve a wavelength-independent absorptivity of up to 50 %, depending on the dielectric properties of the unde…

Impedance-Matched Planar Metamaterial Beam Steerer for Terahertz Waves

Planar metamaterials with tailorable electromagnetic properties in the terahertz domain offer customized optics solutions that are needed for the development of imaging and spectroscopy systems. In particular, metamaterials carry the potential to substitute conventional bulky optics or can be basic building blocks for completely novel devices. In this respect it is advantageous that metamaterials can be devised to be impedance-matched to another material regarding their electromagnetic properties. Here, we design, fabricate and investigate a metamaterial with tailorable refractive index and im…

采用各向异性降低与阻抗失配优化的变换光学方法的平面双极化毫米波龙伯透镜天线

A Flat Dual-Polarized Millimeter-Wave Luneburg Lens Antenna Using Transformation Optics with Reduced Anisotropy and Impedance Mismatch

本研究基于变换光学设计了Ka波段低各向异性、阻抗匹配优化的平面双极化毫米波龙伯透镜天线，搭配超表面相控阵馈源，兼具高增益、宽频带、大扫描角等优势，适用于B5G与雷达感知的机载系统。

最小化非磁性隐身衣的散射

Minimizing the scattering of a non-magnetic cloak

无磁隐身衣提供了一种可行的方法，利用只有电响应的材料实现在光频率下的隐身。在这封信中，我们提出了一个近似的理想隐身斗篷和定量研究其电磁特性的全波散射理论。结果表明，阻抗匹配隐身衣的前向散射随隐身衣厚度的减小而显著增大。尽管如此，仍然有可能有效地减少总散射截面与一个非常薄的斗篷，其阻抗不匹配的外边界处的周围材料。我们的分析还提供了减少在任意方向上的散射的灵活性。

近场平板透镜三维亚波长聚焦

Three Dimensional Subwavelength focus by a near-field plate lens

我们采用逆向设计的方法来构造一个薄的近场透镜，它可以通过操纵磁偶极子源的近场来产生所需的亚波长聚焦。人工阻抗表面所代表的平面近场透镜是由集总电抗元件（电容器和电感器）与空间变化的值。在实验中，获得了所需的环形聚焦光斑，其特征尺寸比衍射极限所允许的尺寸小近三倍。除了高分辨率成像，所提出的近场板可以扩展到其他有趣的应用，如无线电力传输或复杂的波前/波束成形器。

与自由空间匹配的三维返波网络

A three-dimensional backward-wave network matched with free space

设计了一种基于电容和电感负载的三维传输线网络的返波板，以获得与自由空间的阻抗匹配。为了使场能够从自由空间传播到网络，反之亦然，提出了过渡层的使用。匹配的设计网络与自由空间和负折射发生在平板界面确认与全波模拟。

Enhanced light collection from a gallium nitride color center using a near index-matched solid immersion lens

Among the wide-bandgap compound semiconductors, gallium nitride is the most widely available material due to its prevalence in the solid state lighting and high-speed/high-power electronics industries. It is now known that GaN is one of only a handful of materials to host color centers that emit quantum light at room temperature. In this paper, we report on a bright color center in a semi-polar gallium nitride substrate, emitting at room temperature in the near-infrared. We show that a hemispherical solid immersion lens, near index matched to the semiconductor, can be used to enhance the photo…

三维各向同性透射线透镜的亚波长分辨率

Subwavelength resolution with three-dimensional isotropic transmission-line lenses

研究了一种各向同性三维平面透镜（“超透镜”）的色散、阻抗匹配和分辨率特性。该透镜基于互连传输线和大容量负载的立方体网格。我们研究了一种基于微带技术的透镜的实际实现。色散方程，以前已经推导出，与全波模拟进行了验证。分析和仿真结果验证了该结构的各向同性。解析地研究了一种实际可实现的有耗透镜的分辨率特性。

基于LC加载传输线的三维各向同性理想透镜

Three-dimensional isotropic perfect lens based on LC-loaded transmission lines

提出了一种基于互连传输线和大负载立方网格的各向同性三维理想透镜。晶状体由放置在两个类似的未加载网格之间的加载网格的板形成。文中给出了网格中本征波的色散方程和特征阻抗的解析表达式，强调了一般性。这允许设计具有所需色散特性的传输线网格。透镜中所需的反向波操作模式通过简单的电感和电容负载实现。推导了通过透镜的透射率的解析表达式，并证明了倏逝波的放大。研究了影响倏逝波在透镜中增强的因素，建立了相应的设计准则。一个可能的实现的结构进行了概述。

极限环控制时空变化材料中的波能积累

Limit cycles govern wave energy accumulation in space-time-varying materials

该研究通过分析波动方程特征曲线动力学，证明时空变化材料中稳定极限环可吸引特征曲线以积累波能，提出Floquet-Fourier数值方法并经全波模拟验证。