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Related papers: Enhanced Near-cloak by FSH Lining

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Transformation optics constructions have allowed the design of cloaking devices that steer electromagnetic, acoustic and quantum waves around a region without penetrating it, so that this region is hidden from external observations. The…

Analysis of PDEs · Mathematics 2015-09-15 Matti Lassas , Ting Zhou

We theoretically and numerically demonstrate that hydrodynamic cloaking can be achieved by simply adjusting the geometric depth of a region surrounding an object in microscale flow, rendering the external flow field undisturbed. Using the…

Fluid Dynamics · Physics 2025-06-23 Hongyu Liu , Zhi-Qiang Miao , Guang-Hui Zheng

In this paper, we establish approximate cloaking for the heat equation via transformation optics. We show that the degree of visibility is of the order $\epsilon$ in three dimensions and $|\ln\epsilon|^{-1}$ in two dimensions, where…

Analysis of PDEs · Mathematics 2018-11-02 Hoai-Minh Nguyen , Tu Nguyen

Conformal invisibility devices are only supposed to work within the validity range of geometrical optics. Here we show by numerical simulations and analytical arguments that for certain quantized frequencies they are nearly perfect even in…

Optics · Physics 2015-05-27 Huanyang Chen , Ulf Leonhardt , Tomas Tyc

In this paper, we design a truly exact and optimal perfect absorbing layer (PAL) for domain truncation of the two-dimensional Helmholtz equation in an unbounded domain with bounded scatterers. This technique is based on a complex…

Numerical Analysis · Mathematics 2019-10-22 Zhiguo Yang , Li-Lian Wang , Yang Gao

We construct a regular isotropic approximate cloak for the Maxwell system of equations. The method of transformation optics has enabled the design of electromagnetic parameters that cloak a region from external observation. However, these…

Analysis of PDEs · Mathematics 2018-05-23 Tuhin Ghosh , Ashwin Tarikere

Based on a coordinate transformation approach, Pendry {\it et al.} have reported electromagnetically anisotropic and inhomogeneous shells that, in theory, completely shield an interior structure of arbitrary size from electromagnetic fields…

There has recently been considerable interest in the possibility, both theoretical and practical, of invisibility (or "cloaking") from observation by electromagnetic (EM) waves. Here, we prove invisibility, with respect to solutions of the…

Analysis of PDEs · Mathematics 2009-11-11 Allan Greenleaf , Yaroslav Kurylev , Matti Lassas , Gunther Uhlmann

The aim of this paper is to provide an original method of constructing very effective near-cloaking structures for the conductivity problem. These new structures are such that their first Generalized Polarization Tensors vanish. We show…

Mathematical Physics · Physics 2015-05-27 Habib Ammari , Hyeonbae Kang , Hyundae Lee , Mikyoung Lim

At any energy E > 0, we construct a sequence of bounded potentials $V^E_{n}, n\in\N$, supported in an annular region $B_{out}\setminus B_{inn}$ in three-space, which act as approximate cloaks for solutions of Schr\"odinger's equation: For…

Mathematical Physics · Physics 2008-12-10 Allan Greenleaf , Yaroslav Kurylev , Matti Lassas , Gunther Uhlmann

Non-Euclidean geometry combined with transformation optics has recently led to the proposal of an invisibility cloak that avoids optical singularities and therefore can work, in principle, in a broad band of the spectrum [U. Leonhardt and…

Optics · Physics 2014-06-16 Tomas Tyc , Huanyang Chen , Che Ting Chan , Ulf Leonhardt

Transformation optics (TO) is a powerful tool for the design of artiffcial materials with unprecedented optical properties. Here, we propose the approximation of TO structures of arbitrary shape by faceting, in which curved surfaces are…

A crucial part of successful wave propagation related inverse problems is an efficient and accurate numerical scheme for solving the seismic wave equations. In particular, the numerical solution to a multi-dimensional Helmholtz equation can…

Numerical Analysis · Mathematics 2021-03-11 Hatef Dastour , Wenyuan Liao

Nonmagnetic cloak offers a feasible way to achieve invisibility at optical frequencies using materials with only electric responses. In this letter, we suggest an approximation of the ideal nonmagnetic cloak and quantitatively study its…

Optics · Physics 2010-06-01 Jingjing Zhang , Yu Luo , Niels Asger Mortensen

The paper addresses an important issue of cloaking transformations for fourth-order partial differential equations representing flexural waves in thin elastic plates. It is shown that, in contrast with the Helmholtz equation, the general…

Classical Physics · Physics 2015-12-22 D. J. Colquitt , M. Brun , M. Gei , A. B. Movchan , N. V. Movchan , I. S. Jones

Using the framework of transformation optics, this paper presents a detailed analysis of a non-singular square cloak for acoustic, out-of-plane shear elastic, and electromagnetic waves. The generating map is examined in detail and linked to…

Mathematical Physics · Physics 2014-01-30 DJ Colquitt , IS Jones , NV Movchan , AB Movchan M Brun , RC McPhedran

This paper introduces a new sweeping preconditioner for the iterative solution of the variable coefficient Helmholtz equation in two and three dimensions. The algorithms follow the general structure of constructing an approximate $LDL^t$…

Numerical Analysis · Mathematics 2010-08-03 Björn Engquist , Lexing Ying

We design a device that generates fields canceling out a known probing field inside a region to be cloaked while generating very small fields far away from the device. The fields we consider satisfy the Laplace equation, but the approach…

Mathematical Physics · Physics 2015-06-03 Fernando Guevara Vasquez , Graeme W. Milton , Daniel Onofrei

The invisibility cloak has been a long-standing dream for many researchers over the decades. By transforming space and light propagation, a three-dimensional (3D) object can be perceived as having reduced number of dimensions, in the form…

Optics · Physics 2010-03-18 Fan Zhou , Yongjun Bao , Wei Cao , Jianqiang Gu , Weili Zhang , Cheng Sun

In a recent Letter, Cummer et al. give a description of material parameters for acoustic wave propagation giving rise to a 3D spherical cloak, and verify the cloaking phenomenon on the level of scattering coefficients. A similar…

Optics · Physics 2008-01-23 Allan Greenleaf , Yaroslav Kurylev , Matti Lassas , Gunther Uhlmann