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Related papers: Transformation devices: carpets in space and space…

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We consider how transformation optics and invisibility cloaking can be used to construct models in subsets $\mathbb{R}^3$ with a varying metric, where the time-harmonic waves for a given angular wavenumber $k$, are equivalent to the waves…

Analysis of PDEs · Mathematics 2021-03-26 Tracey Balehowsky , Matti Lassas , Pekka Pankka , Ville Sirviö

Recently we have suggested that two-dimensional broadband transformation optics devices based on metamaterial designs may be built using tapered waveguides. Here we review application of this principle to broadband electromagnetic cloaking,…

The onset of transformation optics has opened avenues for designing of a plenitude of applications related to propagation of electromagnetic waves in anisotropic media. In this paper, an algorithm is proposed using a coordinate…

Optics · Physics 2015-11-30 H. H. Sidhwa , R. P. Aiyar , S. V. Kulkarni

Carpets under consideration here, in the context of pressure acoustic waves propagating in a compressible fluid, do not touch the ground: they levitate in mid-air (or float in mid-water), which leads to approximate cloaking for an object…

Optics · Physics 2010-05-19 Andre Diatta , Guillaume Dupont , Sebastien Guenneau , Stefan Enoch

Electromagnetic waves undergo multiple uncontrollable alterations as they propagate within a wireless environment. Free space path loss, signal absorption, as well as reflections, refractions and diffractions caused by physical objects…

Signal Processing · Electrical Eng. & Systems 2018-06-06 Christos Liaskos , Shuai Nie , Ageliki Tsioliaridou , Andreas Pitsillides , Sotiris Ioannidis , Ian Akyildiz

In this paper, we propose a continuously tunable acoustic metasurface composed of identical anisotropic resonant units, each of which contains a rigid pedestal and a rotatable inclusion with space coiling-up structure. The metasurface can…

Applied Physics · Physics 2020-02-11 Haozhen Zou , Yanlong Xu , Pan Li , Pai Peng

The transfer matrix method remains a simple yet powerful tool for modeling acoustic systems, particularly in a closed waveguide geometry. Here we present a generalisation of this method based on the theory of mode matching, that…

Applied Physics · Physics 2025-04-07 D. Cidlinsky , G. J. Chaplain , S. A. R. Horsley

We first note it is possible to construct two linear operators defined on two different domains, yet sharing the same spectrum using a geometric transform. However, one of these two operators will necessarily have spatially varying, matrix…

Fluid Dynamics · Physics 2011-10-03 Guillaume Dupont , Sebastien Guenneau , Stefan Enoch

In recent years a remarkable progress was made in the construction of spatial cloaks using the methods of transformation optics and metamaterials. The temporal cloaking, i.e. the cloaking of an event in spacetime, was also widely studied by…

Mathematical Physics · Physics 2019-02-12 Gregory Eskin

We explore the propagation and transformation of electromagnetic waves through spatially homogeneous yet smoothly time-dependent media within the framework of classical electrodynamics. By modelling the smooth transition, occurring during a…

With the explosion of wireless networks and automotive radar systems, there is an acute need for new materials and technologies that would not only minimize the size of these devices, but also enhance their performances. The technique of…

Materials Science · Physics 2011-04-14 Tichit Paul-Henri , Shah Nawaz Burokur , Dylan Germain , Andre de Lustrac

We extend effective medium theory (EMT) to time-modulated, frequency-dispersive acoustic metamaterials with multiple resonances. While previous studies focused on non-dispersive or single-resonance systems, advances in programmable…

Applied Physics · Physics 2025-05-12 Xinghong Zhu , Hong-Wei Wu , Jensen Li

Cloaking elastic waves has, in contrast to the cloaking of electromagnetic waves, remained a fundamental challenge: the latter successfully uses the invariance of Maxwell's equations, from which the field of transformational optics has…

Materials Science · Physics 2020-11-17 Davide Enrico Quadrelli , Richard Craster , Muamer Kadic , Francesco Braghin

Spatiotemporal metasurfaces offer unique opportunities for wave manipulation, however, their practical realization is often constrained by the requirement for in-plane spatial modulation, which necessitates a large number of time-varying…

Emerging multiphysics metamaterials offer a distinct possibility for regulating complex physical processes. However, two severe constraints still lower their functionality and tunability. First, multiphysics functionality is fixed once…

Applied Physics · Physics 2023-02-02 Min Lei , Liujun Xu , Jiping Huang

The conventional description of time-varying media assumes that electromagnetic fields evolve according to fixed continuity conditions during parameter jumps. Here we reveal that these conditions are not physical constraints but tunable…

Optics · Physics 2026-03-24 Yongge Wang , Jingfeng Yao , Ying Wang , Chengxun Yuan , Zhongxiang Zhou

We develop the theory of acoustic wave propagation in a waveguide containing an array of time modulated digital meta-atoms, showing the equivalence between this array and a homogeneous, time varying, dispersive material. In the limit of an…

Classical Physics · Physics 2021-09-30 S. A. R. Horsley

In this paper various extensions of the design strategy of transformation media are proposed. We show that it is possible to assign different transformed spaces to the field strength tensor (electric field and magnetic induction) and to the…

Optics · Physics 2009-03-04 L. Bergamin

Diffusion metamaterials with artificial spatial structures have significant potential in controlling energy and mass transfer. Those static structures may lead to functionality and tunability constraints, impeding the application scope of…

Applied Physics · Physics 2024-05-30 Jinrong Liu , Liujun Xu , Jiping Huang

A transformation optics approach was used to derive a general method for designing electromagnetic devices able to manipulate the wave vectors in the specific manner required by the functionality of the device. While the wave paths inside…

Optics · Physics 2017-07-19 Mircea Giloan