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The ability to design passive structures that perform different operations on different electromagnetic fields is key to many technologies, from beam-steering to optical computing. While many techniques have been developed to optimise…

Applied Physics · Physics 2022-11-28 J. R. Capers , S. J. Boyes , A. P. Hibbins , S. A. R. Horsley

In this paper we study microstrip antenna miniaturization using partial filling of the antenna volume with dielectric materials. An analytical expression is derived for the quality factor of an antenna loaded with a combination of two…

Classical Physics · Physics 2007-05-23 Olli Luukkonen , Pekka Ikonen , Sergei Tretyakov

We demonstrate that spectrally diverse multiple magnetic dipole resonances can be excited in all-dielectric structures lacking rotational symmetry, in contrast to conventionally used spheres, disks or spheroids. Such multiple magnetic…

Modern antenna design for communication systems revolves around two extremes: devices, where only a small region is dedicated to antenna design, and base stations, where design space is not shared with other components. Both imply different…

Signal Processing · Electrical Eng. & Systems 2022-11-16 Casimir Ehrenborg , Mats Gustafsson

The concepts of many optical devices are based on the fundamental physical phenomena such as resonances. One of the commonly used devices is an electromagnetic antenna that converts localized energy into freely propagating radiation and…

Using adaptive algorithms, the design of nano-scale dielectric structures for photonic applications is explored. Widths of dielectric layers in a linear array are adjusted to match target responses of optical transmission as a function of…

Condensed Matter · Physics 2009-11-10 Yu Chen , Rong Yu , Weifei Li , Omid Nohadani , Stephan Haas , A. F. J. Levi

Recently emerged dielectric resonators and metasurfaces offer a low-loss platform for efficient manipulation of electromagnetic waves from microwave to visible. Such flat meta-optics can focus electromagnetic waves, generate structured…

This paper presents the design of a dual band rectangular Dielectric Resonator Antenna (DRA) coupled to narrow slot aperture that is fed by microstrip line. The fundamental TE111 mode and higher-order TE113 mode are excited with their…

Other Computer Science · Computer Science 2013-06-07 H. Raggad , M. Latrach , A. Gharsallah , T. Razban

Cooperative optical effects are enabled and controlled by interactions between molecular dipoles, meaning that their mutual orientation is of paramount importance to, for example, superabsorbing light-harvesting antennas. Here we show how…

Optics · Physics 2025-02-27 Adam Burgess , Madeline C. Waller , Erik M. Gauger , Robert Bennett

Millimeter wave (mm-wave) communications is considered a promising technology for 5G networks. Exploiting beamforming gains with large-scale antenna arrays to combat the increased path loss at mm-wave bands is one of its defining features.…

Information Theory · Computer Science 2017-04-21 Xianghao Yu , Jun Zhang , Martin Haenggi , Khaled B. Letaief

Extreme field localization and giant field enhancement are often achieved by using plasmonic nanostructures and metamaterials such as strongly coupled silver nanoparticles.Dielectric particles and structures can focus light beyond the…

The spherical nature of the wavefronts exhibited in the near-field of antenna arrays enables advanced beamforming capabilities, such as beampointing and beamnulling. In this paper, we exploit these properties to design a near-field beam…

Signal Processing · Electrical Eng. & Systems 2026-02-16 Laurence Defraigne , Gilles Monnoyer , Jérôme Louveaux , Luc Vandendorpe

Far-field shaping of small antennas is a challenge and the realizations of non-dipole radiation of small to intermediate sized antennas are difficult. Here we examine the antenna bandwidth cost associated with such constraints, and in…

Applied Physics · Physics 2018-08-28 Shuai Shi , Lei Wang , B. L. G. Jonsson

We show theoretically that the characteristic modes of dielectric resonator antennas (DRAs) must be capacitive in the low frequency limit, and show that as a consequence of this constraint and the Poincar\'{e} Separation Theorem, the modes…

Applied Physics · Physics 2021-08-30 Binbin Yang , Jaewoo Kim , Jacob J. Adams

A simple experiment is presented which indicates that electromagnetic fields propagate superluminally in the near-field next to an oscillating electric dipole source. A high frequency 437MHz, 2 watt sinusoidal electrical signal is…

General Physics · Physics 2007-05-23 William D. Walker

Dynamic Metasurface Antennas (DMAs) are recently attracting considerable research interests due to their potential to enable low-cost, reconfigurable, and highly scalable antenna array architectures for next generation wireless systems.…

Signal Processing · Electrical Eng. & Systems 2026-04-14 Ioannis Gavras , George C. Alexandropoulos

Antennas typically have emission/radiation efficiencies bounded by A/(lambda)^2 (A < lambda^2) where A is the emitting area and lambda is the wavelength of the emitted wavelength. That makes it challenging to miniaturize antennas to extreme…

Applied Physics · Physics 2023-02-10 J. L. Drobitch , A. De , K. Dutta , P. K. Pal , A. Adhikari , A. Barman , S. Bandyopadhyay

We reveal the existence of optical super-resonance modes supported by dielectric microspheres. These modes,with field-intensity enhancement factors on the order of 10^4-10^5, can be directly obtained from analytical calculations. In…

The design of far-field radiation diagrams from combined electric and magnetic dipolar sources has recently found applications in nanophotonic metasurfaces that realize tailored reflection and refraction. Such dipolar sources also exhibit…

In the present paper we discuss antenna miniaturization using magneto-dielectric substrates. Recent results found in the literature reveal that advantages over conventional dielectric substrates can only be achieved if natural magnetic…

Classical Physics · Physics 2009-11-11 Pekka Ikonen , Konstantin Rozanov , Alexey Osipov , Sergei Tretyakov