One path to acoustic cloaking
Steven A. Cummer,David Schurig +1 more
Reads0
Chats0
TLDR
In this paper, it was shown that the acoustic equations in a fluid are identical in form to the single polarization Maxwell equations via a variable exchange that also preserves boundary conditions, and the existence of transformation-type solutions for the 2D acoustic equations with anisotropic mass via time harmonic simulations of acoustic cloaking.Abstract:
A complete analysis of coordinate transformations in elastic media by Milton et al has shown that, in general, the equations of motion are not form invariant and thus do not admit transformation-type solutions of the type discovered by Pendry et al for electromagnetics. However, in a two-dimensional (2D) geometry, the acoustic equations in a fluid are identical in form to the single polarization Maxwell equations via a variable exchange that also preserves boundary conditions. We confirm the existence of transformation-type solutions for the 2D acoustic equations with anisotropic mass via time harmonic simulations of acoustic cloaking. We discuss the possibilities of experimentally demonstrating acoustic cloaking and analyse why this special equivalence of acoustics and electromagnetics occurs only in 2D.read more
Citations
More filters
Book ChapterDOI
Acoustics in 2D Spaces of Constant Curvature
TL;DR: In this article, a variational approach on how to model acoustic wave propagation on this particular curved spacetime is presented. But the experimental results are limited to the (2 + 1)D spacetime with Lorentzian signature.
Journal ArticleDOI
Study on Band Gap Characteristics of Boat-Shaped Phononic Crystal
Jia Xu,Yabing Li,Youdi Kuang +2 more
TL;DR: In this paper , the authors analyzed the two-dimensional boat-shaped structure based on the finite element method and found that the structure has band gaps at both high and low frequencies, and they studied the influence of four key parameters, such as the rod length and the angle between the rods, on the bandgap.
Journal ArticleDOI
Design method and infeasibility criteria for honeycomb pentamode cloak
Gen Li,Yan Chen,Huanlong He +2 more
TL;DR: Based on the analytical formula of equivalent mechanical parameters, a design method of honeycomb pentamode circular cloak for linear mapping is presented in this paper , where three inequalities based on extreme values are also proposed as infeasibility criteria.
Journal ArticleDOI
Visco-thermal Effects on Anisotropic and Isotropic Labyrinthine Acoustic Metamaterials in the Cascade
Design of Arbitrarily Shaped Inertial and Three Dimensional Pentamode Acoustic Cloaks
TL;DR: In this article, the authors proposed a method of designing 2D inertial acoustic cloaks having arbitrary shapes, based on transformation acoustics to map along radial directions, which can make a space acoustically invisible.
References
More filters
Journal ArticleDOI
Magnetism from conductors and enhanced nonlinear phenomena
TL;DR: In this paper, it was shown that microstructures built from nonmagnetic conducting sheets exhibit an effective magnetic permeability /spl mu/sub eff/, which can be tuned to values not accessible in naturally occurring materials.
Journal ArticleDOI
Controlling Electromagnetic Fields
TL;DR: This work shows how electromagnetic fields can be redirected at will and proposes a design strategy that has relevance to exotic lens design and to the cloaking of objects from electromagnetic fields.
Journal ArticleDOI
Metamaterial Electromagnetic Cloak at Microwave Frequencies
David Schurig,Jack J. Mock,B.J. Justice,Steven A. Cummer,John B. Pendry,Anthony F. Starr,David R. Smith +6 more
TL;DR: This work describes here the first practical realization of a cloak of invisibility, constructed with the use of artificially structured metamaterials, designed for operation over a band of microwave frequencies.
Journal ArticleDOI
Optical Conformal Mapping
TL;DR: A general recipe for the design of media that create perfect invisibility within the accuracy of geometrical optics is developed, which can be applied to escape detection by other electromagnetic waves or sound.
Journal ArticleDOI
Ultrasonic metamaterials with negative modulus
Nicholas X. Fang,Dongjuan Xi,Jianyi Xu,Muralidhar Ambati,Werayut Srituravanich,Cheng Sun,Xiang Zhang +6 more
TL;DR: A new class of ultrasonic metamaterials consisting of an array of subwavelength Helmholtz resonators with designed acoustic inductance and capacitance with an effective dynamic modulus with negative values near the resonance frequency is reported.