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Optical funnel: broadband and uniform compression of electromagnetic fields to an air neck
Fei Sun,Yichao Liu,Yibiao Yang +2 more
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TLDR
In this paper, an optical funnel is designed by precisely filling subwavelength ceramic blocks with a gradient refractive index inside a tapered waveguide, which is isotropic and all above unit.Abstract:
An optical funnel, which performs as a passive electromagnetic compressor, can guide electromagnetic waves from a wide inlet to a narrow outlet without reflectance/scattering and squeeze electromagnetic fields uniformly to an air neck. In this study, an optical funnel is designed by precisely filling subwavelength ceramic blocks with a gradient refractive index inside a tapered waveguide. The gradient refractive index is designed by transformation optics, which is isotropic and all above unit, thus exhibiting a broadband feature. Due to the mechanism of impedance matching over the whole funnel, extremely low reflectance/scattering and stable enhancement of fields can be achieved. The field enhancement factor in different regions of the funnel (e.g., in the air neck) can be flexibly designed just by modifying the funnel-width ratios.read more
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Artificial Perfect Electric Conductor-Perfect Magnetic Conductor Anisotropic Metasurface for Generating Orbital Angular Momentum of Microwave with Nearly Perfect Conversion Efficiency
TL;DR: In this article, the authors proposed two types of PEC (perfect electric conductor)-PMC (perfect magnetic conductor) anisotropic metasurfaces for OAM generation, one composed of azimuthally continuous loops and the other constructed by azimythally discontinuous dipole scatterers.
Journal ArticleDOI
Near-zero-index-featured Multi-band Highly Directional Radiator with Large Purcell Factors
TL;DR: In this article , a near-zero-index-featured resonator based on optical conformal mapping is proposed to achieve highly directional radiation by using dielectrics with refractive index n ≥ 1.
References
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Journal ArticleDOI
Approaching the Yablonovitch limit with free-floating arrays of subwavelength trumpet non-imaging light concentrators driven by extraordinary low transmission
TL;DR: This study uses finite-difference time-domain electromagnetic calculations to examine the optical response of an infinite cubic-tiled substrate-less silicon trumpet array under normal illumination and shows superior broadband absorption of solar radiation in trumpet arrays (with unoptimized geometry) compared with that of the optimized NP arrays.
Journal ArticleDOI
A feasible approach to field concentrators of arbitrary shapes
TL;DR: In this article, a simple method to design field concentrators of arbitrary shapes based on Fabry-Perot resonances is proposed, and the material parameters are feasible in terms of metallic layered structures and gradient index dielectrics.
Journal ArticleDOI
Topological Fulde-Ferrell and Larkin-Ovchinnikov states in spin-orbit-coupled lattice system
Yao-Wu Guo,Yan Chen +1 more
TL;DR: In this article, a spin-orbit coupled lattice system under Zeeman fields provides an ideal platform to realize exotic pairing states such as Fulde-Ferrell (FF) and Larkin-Ovchinnikov (LO) states.
Journal ArticleDOI
Visible perfect reflectors realized with all-dielectric metasurface
TL;DR: In this paper, the Mie resonances of high-index amorphous titanium dioxide (α TiO 2 ) metasurface arrays were used as back reflectors to enhance light absorption.
Journal ArticleDOI
Realization of a broadband electromagnetic gateway at microwave frequencies
TL;DR: In this article, the authors proposed and experimentally demonstrated a broadband illusion device using crossed split-ring resonator and wire unit cells, which can provide the desirable double-negative parameters through fine geometrical designs.