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Thomas Mulkey, Jimmy Dillies, Maxim Durach
We formulate and solve the inverse problem of quartic photonics, or photonics of metamaterials, whose k-surfaces (also known as iso-frequency surfaces or Fresnel surfaces) are quartic surfaces. This provides an approach to engineer the effective parameters of metamaterials starting from the desired plane waves. We apply our method to the design of the high-k limit of metamaterials, extreme non-reciprocity, and complex bi-anisotropic media.
March 15, 2018: Optics Letters
Yang Shen, Jieqiu Zhang, Yongqiang Pang, Lin Zheng, Jiafu Wang, Hua Ma, Shaobo Qu
Distilled water has frequency dispersive characteristic and high value of imaginary part in permittivity, which can be seen as a good candidate of broadband metamaterial absorbers(MAs) in microwave. Here, an interesting idea based on the combination of water-substrate and metallic metamaterial in the three-dimensional construction is proposed, which can achieve outstanding broadband absorption. As a proof, the distilled water is filled into the dielectric reservoir as ultra-thin water-substrate, and then the water-substrates are arranged on the metal backplane periodically as three-dimensional water-substrate array(TWA)...
March 13, 2018: Scientific Reports
Devin Powell
No abstract text is available yet for this article.
March 13, 2018: Proceedings of the National Academy of Sciences of the United States of America
Hai Lin, Wenguo Zhu, Jianhui Yu, Mengjiang Jiang, Linqing Zhuo, Wentao Qiu, Jiangli Dong, Yongchun Zhong, Zhe Chen
The angular Goos-Hänchen shift of vortex beam is investigated theoretically when a Laguerre-Gaussian (LG) beam is reflected by an air-metamaterial interface. The upper limit of the angular GH shift is found to be half of the divergence angle of the incident beam, i.e., |Θup| = (|ℓ| + 1)1/2 /k0 w0 , with ℓ, k0 , and w0 being the vortex charge, wavenumber in vacuum, and beam waist, respectively. Interestingly, the upper limited angular GH shift is accompanied by the upper-limited spatial IF shift. A parameter F is introduced to compare the total beam shift with the beam size...
March 5, 2018: Optics Express
Jing Wang, Hao Tian, Yu Wang, Xueyan Li, Yujie Cao, Li Li, Jianlong Liu, Zhongxiang Zhou
An electrically tunable terahertz (THz) modulator with large modulation depth and low insertion loss is performed with liquid crystal (LC) metamaterial. The modulation depth beyond 90% and insertion loss below 0.5 dB are achievable at normal incidence by exploiting plasmon-induced transparency (PIT) effect. The PIT spectra can be manipulated by actively controlling the interference between dipole mode and nonlocal surface-Bloch mode with LC. The incident angle tuning effect on PIT spectra shows that the large modulation depth and low insertion loss can remain over a wide range of working angles...
March 5, 2018: Optics Express
Lei Lei, Shun Li, Haixuan Huang, Keyu Tao, Ping Xu
We propose a design of an ultra-broadband absorber based on a thin metamaterial nanostructure composed of a periodic array of titanium-silica (Ti-SiO2 ) cubes and an aluminum (Al) bottom film. The proposed structure can achieve nearly perfect absorption with an average absorbance of 97% spanning a broad range from visible to near-infrared (i.e., from 354 nm to 1066 nm), showing a 90% absorption bandwidth over 712 nm, and the peak absorption is up to 99.8%. The excitation of superior surface plasmon resonance combined with the resonance induced by the metal-insulator-metal Fabry-Perot (FP) cavity leads to this broadband perfect absorption...
March 5, 2018: Optics Express
Shinpei Ogawa, Masaaki Shimatani, Shoichiro Fukushima, Satoshi Okuda, Kazuhiko Matsumoto
Metal-insulator-metal-based plasmonic metamaterial absorbers (MIM-PMAs) generate strong localized surface plasmon resonance (LSPR) on their surfaces. Therefore, MIM-PMAs are expected to enhance the absorption of graphene coated on their surfaces. Graphene-coated MIM-PMAs (GMIM-PMAs) were developed and their optical properties were investigated both experimentally and numerically at infrared wavelengths. Significant modification of the absorption of GMIM-PMAs was achieved only in the main LSPR wavelength region, where the insulator is lossless...
March 5, 2018: Optics Express
Zhigang Li, Liliana Stan, David A Czaplewski, Xiaodong Yang, Jie Gao
Wavelength-selective metamaterial absorbers in the mid-infrared range are demonstrated by using multiple tungsten cross resonators. By adjusting the geometrical parameters of cross resonators in single-sized unit cells, near-perfect absorption with single absorption peak tunable from 3.5 µm to 5.5 µm is realized. The combination of two, three, or four cross resonators of different sizes in one unit cell enables broadband near-perfect absorption at mid-infrared range. The obtained absorption spectra exhibit omnidirectionality and weak dependence on incident polarization...
March 5, 2018: Optics Express
Xianglian Song, Zizhuo Liu, Yuanjiang Xiang, Koray Aydin
Most of hyperbolic metamaterials (HMMs) investigated to date are based on isotropic materials resulting in uniaxial HMMs in which dielectric permittivities perpendicular to the propagation direction are the same. Using an anisotropic material constituent to form a HMM is a promising research direction providing opportunities to control the dielectric permittivity in all three directions independently. Herein, we propose and theoretically demonstrate novel biaxial HMMs composed of multilayer stacks of few-layer black phosphorus (BP) and Au thin films...
March 5, 2018: Optics Express
Miller Eaton, Alessandra Catellani, Arrigo Calzolari
VO2 is a unique phase change material with strongly anisotropic electronic properties. Recently, samples have been prepared that present a co-existence of phases and thus form metal-insulator junctions of the same chemical compound. Using first principles calculations, the optical properties of metallic and semiconducting VO2 are here discussed to design self-contained natural optical metamaterials, avoiding coupling with other dielectric media. The analysis of the optical properties complements the experiments in the description of the vast change in reflectance and metallicity for both disordered and planar compounds...
March 5, 2018: Optics Express
Okan Yurduseven, Daniel L Marks, Thomas Fromenteze, David R Smith
We present a reconfigurable, dynamic beam steering holographic metasurface aperture to synthesize a microwave camera at K-band frequencies. The aperture consists of a 1D printed microstrip transmission line with the front surface patterned into an array of slot-shaped subwavelength metamaterial elements (or meta-elements) dynamically tuned between "ON" and "OFF" states using PIN diodes. The proposed aperture synthesizes a desired radiation pattern by converting the waveguide-mode to a free space radiation by means of a binary modulation scheme...
March 5, 2018: Optics Express
Zohreh Vafapour
Recently reported metamaterial (MM) analogs of electromagnetically induced reflectance (EIR) enable a unique route to endow classical optical structures with aspects of quantum optical systems. This method opens up many fascinating prospects on novel optical components, such as slow light units, highly sensitive sensors, and nonlinear devices. Here we designed and simulated a microwave MM made from aluminum thin film to mimic the EIR system. High reflectance of about 99 percent and also a large group index at the reflectance window of about 243 are demonstrated, which mainly arise from the enhanced coupling between radiative and nonradiative elements...
March 1, 2018: Journal of the Optical Society of America. A, Optics, Image Science, and Vision
Hailong Huang, Hui Xia, Wenke Xie, Zhibo Guo, Hongjian Li, Ding Xie
In this paper, a tunable broadband metamaterial absorber (MA) based on graphene is investigated theoretically and numerically at mid-infrared regions. Compared with the previously reported multiband graphene-based MAs, a broad bandwidth of 11.7 THz with the absorption over 90% is obtained in the proposed MA, which is composed of a Jerusalem cross (JC) metal encrusting into the slot graphene layer in the top layer. The results show that the origin of broadband absorption is caused by coupling effect between metal and graphene, and this effect is explained by the two-mode waveguide coupling theory...
March 8, 2018: Scientific Reports
Hongbin Fang, Shih-Cheng A Chu, Yutong Xia, Kon Well Wang
Developing mechanical metamaterials with programmable properties is an emerging topic receiving wide attention. While the programmability mainly originates from structural multistability in previously designed metamaterials, here it is shown that nonflat-foldable origami provides a new platform to achieve programmability via its intrinsic self-locking and reconfiguration capabilities. Working with the single-collinear degree-4 vertex origami tessellation, it is found that each unit cell can self-lock at a nonflat configuration and, therefore, possesses wide design space to program its foldability and relative density...
March 7, 2018: Advanced Materials
Kaikai Che, Chao Yuan, H Jerry Qi, Julien Meaud
When an architected material with snap-through instabilities is loaded, the unit cells of the architected material snap sequentially to a series of deformed configurations. In this paper, we propose the novel concept of multimaterial viscoelastic architected materials whose snapping sequence can be tuned using temperature as a control parameter. Because different polymers have different temperature-dependent properties, it is possible that one polymer that is stiffer than another polymer at one temperature becomes softer at a higher temperature...
March 7, 2018: Soft Matter
Yuan Cao, Valla Fatemi, Ahmet Demir, Shiang Fang, Spencer L Tomarken, Jason Y Luo, J D Sanchez-Yamagishi, K Watanabe, T Taniguchi, E Kaxiras, R C Ashoori, P Jarillo-Herrero
van der Waals heterostructures are an emergent class of metamaterials that consist of vertically stacked two-dimensional building blocks, which provide us with a vast tool set to engineer their properties on top of the already rich tunability of two-dimensional materials.1 One of the knobs, the twist angle between different layers, has a crucial role in the ultimate electronic properties of a van der Waals heterostructure and does not have a direct analogue in other systems such as MBE-grown semiconductor heterostructures...
March 5, 2018: Nature
Dylan Lu, Haoliang Qian, Kangwei Wang, Hao Shen, Feifei Wei, Yunfeng Jiang, Eric E Fullerton, Paul K L Yu, Zhaowei Liu
Semiconductor quantum well (QW) light-emitting diodes (LEDs) have limited temporal modulation bandwidth of a few hundred MHz due to the long carrier recombination lifetime. Material doping and structure engineering typically leads to incremental change in the carrier recombination rate, whereas the plasmonic-based Purcell effect enables dramatic improvement for modulation frequency beyond the GHz limit. By stacking Ag-Si multilayers, the resulting hyperbolic metamaterials (HMMs) have shown tunability in the plasmonic density of states for enhancing light emission at various wavelengths...
March 7, 2018: Advanced Materials
Daniel Rayneau-Kirkhope, Chengzhao Zhang, Louis Theran, Marcelo A Dias
In recent years, many structural motifs have been designed with the aim of creating auxetic metamaterials. One area of particular interest in this subject is the creation of auxetic material properties through elastic instability. Such metamaterials switch from conventional behaviour to an auxetic response for loads greater than some threshold value. This paper develops a novel methodology in the analysis of auxetic metamaterials which exhibit elastic instability through analogy with rigid link lattice systems...
February 2018: Proceedings. Mathematical, Physical, and Engineering Sciences
Wenlong Gao, Biao Yang, Ben Tremain, Hongchao Liu, Qinghua Guo, Lingbo Xia, Alastair P Hibbins, Shuang Zhang
Nodal line semimetals (NLS) are three-dimensional (3D) crystals that support band crossings in the form of one-dimensional rings in the Brillouin zone. In the presence of spin-orbit coupling or lowered crystal symmetry, NLS may transform into Dirac semimetals, Weyl semimetals, or 3D topological insulators. In the photonics context, despite the realization of topological phases, such as Chern insulators, topological insulators, Weyl, and Dirac degeneracies, no experimental demonstration of photonic nodal lines (NLs) has been reported so far...
March 5, 2018: Nature Communications
Shu Chen, Yuejiao Zhang, Tien-Mo Shih, Weimin Yang, Shu Hu, Xiaoyan Hu, Jian-Feng Li, Bin Ren, Bing-Wei Mao, Zhi-Lin Yang, Zhong-Qun Tian
Plasmon-induced magnetic resonance has shown great potentials in optical metamaterials, chemical (bio)-sensing and surface enhanced spectroscopies. Here, we have theoretically and experimentally revealed (1) a correspondence of the strongest near-field response to the far-field scattering valley and (2) a significant improvement in Raman signals of probing molecules by the plasmon-induced magnetic resonance. These revelations are accomplished by designing a simple and practical metallic nanoparticle-film plasmonic system that generates magnetic resonances at visible-near infrared frequencies...
March 5, 2018: Nano Letters
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