Magnetostatic chameleonlike metashells with negative permeabilities

Department of Physics, State Key Laboratory of Surface Physics, and Key Laboratory of Micro and Nano Photonic Structures (MOE), Fudan University - Shanghai 200433, China

^(a) jphuang@fudan.edu.cn

Received: 5 February 2019
Accepted: 15 March 2019

Abstract

Magnetic metamaterials have attracted intensive attention for their extraordinary ability to control magnetic fields. However, almost all magnetic metamaterials exhibit no intelligence. This situation largely results from the fact that permeability, as an inherent property, cannot adapt to nearby changes. Inspired by the chameleon behavior, here we design two types of magnetostatic chameleonlike metashells in two dimensions, which are featured by their adaptive responses to inside objects. One type is based on the anisotropic monolayer scheme, and the other is based on the isotropic bilayer scheme. We derive the requirements of magnetostatic chameleonlike metashells by making the effective permeabilities of the chameleonlike metashells always equal to the permeabilities of inside objects. In both schemes, negative permeabilities are required. Theoretical derivations are validated by finite-element simulations. We further extend the anisotropic monolayer scheme to three dimensions. Magnetostatic chameleonlike metashells can act as a type of all-purpose materials to work under different requirements of permeabilities. This work provides intelligence to permeability, and further intelligent metamaterials beyond chameleonlike metashells can be expected.