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Shuqi Chen Wenwei Liu Zhancheng Li Hua Cheng Jianguo Tian 《Advanced materials (Deerfield Beach, Fla.)》2020,32(3):1805912
Metasurfaces are planar photonic elements composed of subwavelength nanostructures, which can deeply interact with light and exploit new degrees of freedom (DOF) to manipulate optical fields. In the past decade, metasurfaces have drawn great interest from the scientific community due to their profound potential to arbitrarily control light. Here, recent developments of multiplexing and multifunctional metasurfaces, which enable concurrent tasks through a dramatic compact design, are reviewed. The fundamental properties, design strategies, and applications of multiplexing and multifunctional metasurfaces are then discussed. First, recent progress on angular momentum multiplexing, including its behavior under different incident conditions, is considered. Second, a detailed overview of polarization-controlled, wavelength-selective, angle-selective, and reconfigurable multiplexing/multifunctional metasurfaces is provided. Then, the integrated and on-chip design of multifunctional metasurfaces is addressed. Finally, future directions and potential applications are presented. 相似文献
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Manipulation of terahertz wave by metasurfaces has shown tremendous potential in developing compact and functional terahertz optical devices. Here, we propose complementary bilayer metasurfaces for enhanced terahertz wave amplitude and phase manipulation. The metasurfaces are composed of one layer of metal cut-wire arrays and one layer of their complementary aperture arrays separated by a dielectric spacer. Through the near-field coupling between transverse magnetic resonances in the metal apertures and electric resonances in the metal cut-wires, the structures can manipulate the cross polarization conversion and phase dispersion of terahertz wave. Particularly, the designed metasurfaces demonstrate a phase delay of 180° between two orthogonal axes with the same transmission amplitude between 0.70 and 1.0 THz, enabling a 45° broadband polarization conversion. When the metal cut-wires are rotated with respect to the apertures or the thickness of the dielectric spacer is changed, the amplitude and phase dispersion of the transmitted terahertz wave can be tuned. Such complementary coupled bilayer metasurfaces offer a new method to control the amplitude and phase dispersion of terahertz wave and promise great potential for applications in terahertz meta-devices. 相似文献
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James A. Dolan Raphael Dehmel Angela Demetriadou Yibei Gu Ulrich Wiesner Timothy D. Wilkinson Ilja Gunkel Ortwin Hess Jeremy J. Baumberg Ullrich Steiner Matthias Saba Bodo D. Wilts 《Advanced materials (Deerfield Beach, Fla.)》2019,31(2)
Optical metamaterials offer the tantalizing possibility of creating extraordinary optical properties through the careful design and arrangement of subwavelength structural units. Gyroid‐structured optical metamaterials possess a chiral, cubic, and triply periodic bulk morphology that exhibits a redshifted effective plasma frequency. They also exhibit a strong linear dichroism, the origin of which is not yet understood. Here, the interaction of light with gold gyroid optical metamaterials is studied and a strong correlation between the surface morphology and its linear dichroism is found. The termination of the gyroid surface breaks the cubic symmetry of the bulk lattice and gives rise to the observed wavelength‐ and polarization‐dependent reflection. The results show that light couples into both localized and propagating plasmon modes associated with anisotropic surface protrusions and the gaps between such protrusions. The localized surface modes give rise to the anisotropic optical response, creating the linear dichroism. Simulated reflection spectra are highly sensitive to minute details of these surface terminations, down to the nanometer level, and can be understood with analogy to the optical properties of a 2D anisotropic metasurface atop a 3D isotropic metamaterial. This pronounced sensitivity to the subwavelength surface morphology has significant consequences for both the design and application of optical metamaterials. 相似文献
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《Advanced Materials Interfaces》2018,5(12)
Sensing devices for environment, safety, healthcare, and optoelectronic applications require an accurate and noninvasive monitoring of their temperature, because its variations markedly affect the overall response of the device. Monitoring the optical response of temperature‐sensitive integrated photonic elements, such as microresonators or microinterferometers, is an appealing solution in this context. However, achieving high‐resolution optical thermometry with such elements is unpractical and costly as this requires lithography processing, highly monochromatic laser sources, complex light coupling strategies. Here, a photonic‐plasmonic metasurface design that enables practical optical thermometry with a sub‐10−3 °C resolution is proposed. It is based on a self‐assembled nanostructured material implemented with a lithography‐free process. The optical response of the temperature‐sensitive metasurface is probed using a white light source and by monitoring the optical phase in a standard reflectance configuration. This facile, yet powerful, sensing scheme stands on the effective response of the metasurface, which involves the hybridization of thin film interference and low‐quality‐factor plasmon resonances to enable a quasi‐darkness response with a sharp spectral variation (jump) of the optical phase. Such jump is equivalent with a high‐quality‐factor resonator that yields a high sensor responsivity and thus enables high‐resolution optical thermometry. 相似文献
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Hongbao Xin Yuchao Li Dekang Xu Yueli Zhang Chia‐Hung Chen Baojun Li 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(14)
Detecting and analyzing pathogenic bacteria in an effective and reliable manner is crucial for the diagnosis of acute bacterial infection and initial antibiotic therapy. However, the precise labeling and analysis of bacteria at the single‐bacterium level are a technical challenge but very important to reveal important details about the heterogeneity of cells and responds to environment. This study demonstrates an optical strategy for single‐bacterium labeling and analysis by the cotrapping of single upconversion nanoparticles (UCNPs) and bacteria together. A single UCNP with an average size of ≈120 nm is first optically trapped. Both ends of a single bacterium are then trapped and labeled with single UCNPs emitting green light. The labeled bacterium can be flexibly moved to designated locations for further analysis. Signals from bacteria of different sizes are detected in real time for single‐bacterium analysis. This cotrapping method provides a new approach for single‐pathogenic‐bacterium labeling, detection, and real‐time analysis at the single‐particle and single‐bacterium level. 相似文献
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F. Ilinca J.‐F. Htu 《International journal for numerical methods in engineering》2002,53(8):2003-2017
This paper presents a finite element algorithm for solving gas‐assisted injection moulding problems. The filling material is considered incompressible and has temperature and shear rate dependent viscosity. The solution of the three‐dimensional (3D) equations modelling the momentum, mass and energy conservation is coupled with two front‐tracking equations, which are solved for the polymer/air and gas/polymer interfaces. The performances of the proposed procedure are quantified by solving the gas‐assisted injection problem on a thin plate with a flow channel. Solutions are shown for different polymer/gas ratios injected. The effect of the melt temperature, gas pressure and gas injection delay, on the solution behaviour is also investigated. The approach is then applied to a thick 3D part. Published in 2001 by John Wiley & Sons, Ltd. 相似文献
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Bowen Liu Shu Chen Jiancheng Zhang Xu Yao Haixin Lin Tengxiang Huang Zhilin Yang Jinfeng Zhu Shou Liu Christoph Lienau Lei Wang Bin Ren 《Advanced materials (Deerfield Beach, Fla.)》2018,30(12)
Surface plasmon polaritons (SPPs) are extremely sensitive to the surrounding refractive index and have found important applications in ultrasensitive label‐free sensing. Reducing the linewidth of an SPP mode is an effective way to improve the figure of merit (FOM) and hence the sensitivity of the plasmonic mode. Many efforts have been devoted to achieving a narrow linewidth by mode coupling, which inevitably results in an asymmetrical lineshape compromising the performance. Instead, the SPP modes are directly narrowed by elaborately engineering periodic plasmonic structures with minimized feature sizes to effectively reduce the radiative losses. A narrow linewidth smaller than 8 nm is achieved over a wide wavelength ranging from 600 to 960 nm and a minimum full width at half maximum of 3 nm at 960 nm. Benefiting from the almost perfect Lorentzian lineshape and the extremely narrow linewidth, a record FOM value of 730 is obtained. The sensor is capable of detecting bovine serum albumin with an ultralow concentration of 10?10m . The sensor has great potential for practical application for its ultrahigh FOM, broad working wavelength, and ease of high‐throughput fabrication. 相似文献
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In the past centuries, the scale of engineering optics has evolved toward two opposite directions: one is represented by giant telescopes with apertures larger than tens of meters and the other is the rapidly developing micro/nano‐optics and nanophotonics. At the nanoscale, subwavelength light–matter interaction is blended with classic and quantum effects in various functional materials such as noble metals, semiconductors, phase‐change materials, and 2D materials, which provides unprecedented opportunities to upgrade the performance of classic optical devices and overcome the fundamental and engineering difficulties faced by traditional optical engineers. Here, the research motivations and recent advances in subwavelength artificial structures are summarized, with a particular emphasis on their practical applications in super‐resolution and large‐aperture imaging systems, as well as highly efficient and spectrally selective absorbers and emitters. The role of dispersion engineering and near‐field coupling in the form of catenary optical fields is highlighted, which reveals a methodology to engineer the electromagnetic response of complex subwavelength structures. Challenges and tentative solutions are presented regarding multiscale design, optimization, fabrication, and system integration, with the hope of providing recipes to transform the theoretical and technological breakthroughs on subwavelength hierarchical structures to the next generation of engineering optics, namely Engineering Optics 2.0. 相似文献
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D. Wu S. H. Lo N. Sheng K. Y. Sze 《International journal for numerical methods in engineering》2010,81(3):307-334
High‐performance hybrid‐stress hexahedral solid elements are excellent choices for modeling joints, beams/columns walls and thick slabs for building structures if the exact geometrical representation is required. While it is straight‐forward to model beam–column structures of uniform member size with solid hexahedral elements, joining up beams and columns of various cross‐sections at a common point proves to be a challenge for structural modeling using hexahedral elements with specified dimensions. In general, the joint has to be decomposed into 27 smaller solid elements to cater for the necessary connection requirements. This will inevitably increase the computational cost and introduce element distortions when elements of different sizes have to be used at the joint. Universal connection hexahedral elements with arbitrary specified connection interfaces will be an ideal setup to connect structural members of different sizes without increasing the number of elements or introducing highly distorted elements. In this paper, the requirements and the characteristics of the hexahedral connection elements with 24 and 32 nodes will be discussed. Formulation of the connection elements by means of Hellinger–Reissner functional will be presented. The performance of connection elements equipped with different number of stress modes will be assessed with worked examples. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
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Wenbo Zang Quan Yuan Run Chen Lin Li Tianyue Li Xiujuan Zou Gaige Zheng Zhuo Chen Shuming Wang Zhenlin Wang Shining Zhu 《Advanced materials (Deerfield Beach, Fla.)》2020,32(27):1904935
Metasurfaces are 2D metamaterials composed of subwavelength nanoantennas according to specific design. They have been utilized to precisely manipulate various parameters of light fields, such as phase, polarization, amplitude, etc., showing promising functionalities. Among all meta-devices, the metalens can be considered as the most basic and important application, given its significant advantage in integration and miniaturization compared with traditional lenses. However, the resonant dispersion of each nanoantenna in a metalens and the intrinsic chromatic dispersion of planar devices and optical materials result in a large chromatic aberration in metalenses that severely reduces the quality of their focusing and imaging. Consequently, how to effectively suppress or manipulate the chromatic aberration of metalenses has attracted worldwide attention in the last few years, leading to variety of excellent achievements promoting the development of this field. Herein, recent progress in chromatic dispersion control based on metalenses is reviewed. 相似文献
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Joris Lacroix Sandrine Pélofy Charline Blatché Marie‐Jeanne Pillaire Sébastien Huet Catherine Chapuis Jean‐Sébastien Hoffmann Aurélien Bancaud 《Small (Weinheim an der Bergstrasse, Germany)》2016,12(43):5963-5970
DNA replication is essential to maintain genome integrity in S phase of the cell division cycle. Accumulation of stalled replication forks is a major source of genetic instability, and likely constitutes a key driver of tumorigenesis. The mechanisms of regulation of replication fork progression have therefore been extensively investigated, in particular with DNA combing, an optical mapping technique that allows the stretching of single molecules and the mapping of active region for DNA synthesis by fluorescence microscopy. DNA linearization in nanochannels has been successfully used to probe genomic information patterns along single chromosomes, and has been proposed to be a competitive alternative to DNA combing. Yet this conjecture remains to be confirmed experimentally. Here, two complementary techniques are established to detect the genomic distribution of tracks of newly synthesized DNA in human cells by optical mapping in nanochannels. Their respective advantages and limitations are compared, and applied them to detect deregulations of the replication program induced by the antitumor drug hydroxyurea. The developments here thus broaden the field of applications accessible to nanofluidic technologies, and can be used in the future as part for molecular diagnostics in the context of high throughput cancer drug screening. 相似文献
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Kun Huang Fei Qin Hong Liu Huapeng Ye Cheng‐Wei Qiu Minghui Hong Boris Luk'yanchuk Jinghua Teng 《Advanced materials (Deerfield Beach, Fla.)》2018,30(26)
Traditional objective lenses in modern microscopy, based on the refraction of light, are restricted by the Rayleigh diffraction limit. The existing methods to overcome this limit can be categorized into near‐field (e.g., scanning near‐field optical microscopy, superlens, microsphere lens) and far‐field (e.g., stimulated emission depletion microscopy, photoactivated localization microscopy, stochastic optical reconstruction microscopy) approaches. However, they either operate in the challenging near‐field mode or there is the need to label samples in biology. Recently, through manipulation of the diffraction of light with binary masks or gradient metasurfaces, some miniaturized and planar lenses have been reported with intriguing functionalities such as ultrahigh numerical aperture, large depth of focus, and subdiffraction‐limit focusing in far‐field, which provides a viable solution for the label‐free superresolution imaging. Here, the recent advances in planar diffractive lenses (PDLs) are reviewed from a united theoretical account on diffraction‐based focusing optics, and the underlying physics of nanofocusing via constructive or destructive interference is revealed. Various approaches of realizing PDLs are introduced in terms of their unique performances and interpreted by using optical aberration theory. Furthermore, a detailed tutorial about applying these planar lenses in nanoimaging is provided, followed by an outlook regarding future development toward practical applications. 相似文献
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矢量光场由于其独特的光场分布特性,在许多领域都得到了广泛且深入的研究与应用。传统光场调控手段受限于材料的光学特性及物理尺寸,难以实现灵活高效的动态操控功能。超表面凭借其亚波长结构设计所带来的额外自由度,突破了上述局限,使得对矢量光场的振幅、相位、偏振态乃至传播方向等的独立调控成为可能。本文结合国内外矢量光场领域的基础理论及最新进展,系统地阐述了矢量光场的基本原理及其数学模型,重点介绍了目前超表面生成矢量光场的方法,以及这种矢量光场在聚焦、轨道角动量检测、高精度定位等方面应用的具体案例与创新成果。
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