Omnidirectional two-dimensional acoustic cloak by axisymmetric cylindrical lattices

Abstract

We report a two-dimensional acoustic cloak designed with axisymmetric cylindrical lattices. The proposed axisymmetric lattice layers are optimized such that acoustic cloaking can be effectively realized within realistic material properties regardless of the incoming direction of plane waves. The cylindrical shape of lattice structures consists of five layers and each layer is composed of the same number of circular cylinders to form an axisymmetric lattice structure. The present results show that acoustic cloaking with axisymmetric cylindrical lattices can be realized with many advantages such as use of realistic material properties, simplified geometry, omnidirectional cloaking and controllable cloaking degrees.