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Interferometric millimeter observations of the cosmic microwave background and clusters of galaxies with arcmin resolutions require antenna arrays with short spacings. Having all antennas co-mounted on a single steerable platform sets…

Gradient metasurfaces have been extensively applied in recent years for enabling an unprecedented control of light beam over thin optical components. However, these metasurfaces suffer from low efficiency when it comes to bending light with…

Optics · Physics 2020-10-22 Tie-Jun Huang , Li-Zheng Yin , Jin Zhao , Chao-Hai Du , Pu-Kun Liu

We demonstrate a kind of grating coupler that generates high quality flat-top beam with a small beamwidth from photonic integrated circuits into free-space. The grating coupler is designed on a silicon-on-insulator wafer with a 220 nm-thick…

In 6G wireless communications, functional terahertz reflecting metasurfaces are expected to play increasingly important roles such as beamforming and beamsteering. This paper demonstrates the design of a functional and efficient beamforming…

Optics · Physics 2023-06-06 Fahim Ferdous Hossain , John F. OHara

We demonstrate a silicon-based, single-layer anti-reflection coating that suppresses the reflectivity of metals at near-infrared frequencies, enabling optical probing of nano-scale structures embedded in highly reflective surroundings. Our…

Applied Physics · Physics 2024-04-11 M. Pancaldi , R. Freeman , M. Hudl , M. C. Hoffmann , S. Urazhdin , P. Vavassori , S. Bonetti

The transverse radiation pressure force and acceleration is compared for two parametrically optimized designs: prismatic and two-pillar metasurface gratings. The numerical results were cross-verified with both Maxwell stress tensor and…

Optics · Physics 2023-06-27 Prateek R. Srivastava , Ryan M. Crum , Grover A. Swartzlander

The quest for increasing the scanning range of a phased array is a challenging task for antenna engineers, and its solution could lead to significant advances in different applicative scenarios, ranging from 5G and beyond 5G communications…

Reducing electromagnetic scattering from an object has always been a task, inspiring efforts across disciplines such as materials science and electromagnetic theory. The pursuit of electromagnetic cloaking significantly advanced the field…

Diffraction gratings disperse light in a rainbow of colors with the opposite order than refractive prisms, a phenomenon known as negative dispersion. While refractive dispersion can be controlled via material refractive index, diffractive…

Optics · Physics 2017-06-21 Ehsan Arbabi , Amir Arbabi , Seyedeh Mahsa Kamali , Yu Horie , Andrei Faraon

Conventional multistatic radar systems using microwave and millimeter-wave (mm-wave) frequencies seek to reconstruct the target in the imaging domain, employing many transmitting and receiving antenna elements. These systems are suboptimal,…

Applied Physics · Physics 2018-06-20 Ali Molaei , Juan Heredia-Juesas , Galia Ghazi , James Vlahakis , Jose Martinez-Lorenzo

We numerically demonstrate a highly efficient optica huygens metagrating with unprecedentedly simple structure (only one meta-atom per period) designed via aggressively discretized method which initially originated from discretized…

Optics · Physics 2023-04-18 Rui Yao

Designed an elliptical polarization conversion metasurface (PCM) for Ka-band applications, alongside a high-gain substrate integrated waveguide (SIW) antenna. The PCM elements are integrated into the antenna design in a chessboard array…

Systems and Control · Electrical Eng. & Systems 2025-01-07 Cuiqin Zhao , Dongya Shen , Yanming Duan , Yuting Wang , Huihui Xiao , Longxiang Luo

In this paper we propose a novel design approach for an ultrathin metasurface energy harvester based on a surrogate model of dipole antenna. A significant advantage of this idea is the reduction of the time of the design process retrieved…

Applied Physics · Physics 2024-07-19 Alireza Ghaneizadeh , Mojtaba Joodaki , Josef Börcsök , Khalil Mafinezhad

A coupled dielectric-metal metasurface (CDMM) consisting of amorphous silicon (a-$\textit{Si}$) rings and subwavelength holes in $\textit{Au}$ layer separated by a $\textit{SiO}_{2}$ layer is presented. The design parameters of the CDMM is…

Optics · Physics 2020-01-08 Arvind Nagarajan , Koen van Erve , Giampiero Gerini

We develop a simple and reliable analytical model that allows describing the electromagnetic response of all-dielectric metasurfaces consisting of a single-layer array of high-permittivity spherical particles. By combining Mie theory with a…

Classical Physics · Physics 2020-12-21 Alessio Monti , Andrea Alù , Alessandro Toscano , Filiberto Bilotti

We report on the detection of diffraction gratings buried below a stack of tens of 18 nm thick $\mathrm{SiO_2}$ and $\mathrm{Si_3N_4}$ layers and an optically opaque metal layer, using laser-induced, extremely-high frequency ultrasound. In…

We present the design, manufacturing technique, and characterization of a 3D-printed broadband graded index millimeter wave absorber. The absorber is additively manufactured using a fused filament fabrication (FFF) 3D printer out of a…

Instrumentation and Methods for Astrophysics · Physics 2019-02-05 Matthew Petroff , John Appel , Karwan Rostem , Charles L. Bennett , Joseph Eimer , Tobias Marriage , Joshua Ramirez , Edward J. Wollack

We used two novel approaches to produce sub-wavelength structure (SWS) anti-reflection coatings (ARC) on silicon for the millimeter and sub-millimeter (MSM) wave band: picosecond laser ablation and dicing with beveled saws. We produced…

Instrumentation and Methods for Astrophysics · Physics 2017-06-09 Karl Young , Qi Wen , Shaul Hanany , Hiroaki Imada , Jürgen Koch , Tomotake Matsumura , Oliver Suttmann , Viktor Schütz

Dense arrays can facilitate the integration of multiple antennas into finite volumes. In addition to the compact size, sub-wavelength spacing enables superdirectivity for endfire operation, a phenomenon that has been mainly studied for…

Information Theory · Computer Science 2022-08-03 Konstantinos Dovelos , Stylianos D. Assimonis , Hien Quoc Ngo , Michail Matthaiou

This article concerns the design of antireflection structures which, placed on a photonic crystal surface, significantly diminish the fraction of energy lost to reflected waves. After a review of the classes of these structures proposed to…

Optics · Physics 2015-05-30 Wojciech Smigaj , Boris Gralak
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