Experimentally demonstrated an unidirectional electromagnetic cloak designed by topology optimization

TL;DR

This paper reports the experimental realization of a unidirectional electromagnetic cloak using topology optimization, achieving effective cloaking with a simple dielectric material and validating performance through measurements aligned with simulations.

Contribution

It demonstrates the first experimental implementation of a topology-optimized unidirectional electromagnetic cloak with a large invisible region.

Findings

Effective cloaking verified experimentally

Performance matches numerical simulations

Advantages and disadvantages of the optimization method discussed

Abstract

Electromagnetic invisible devices usually designed by transformation optics are rather complicated in material parameters and not suitable for general applications. Recently a topology optimized cloak based on level-set method was proposed to realize nearly perfect cloaking by Fujii et al [Appl. Phys. Lett. 102, 251106 (2013)]. In this work we experimentally implemented this idea and fabricated a unidirectional cloak with a relative large invisible region made of single dielectric material. Good cloaking performance was verified through measurement which consists very well with numerical simulation. The advantages and disadvantages of this optimization method are also discussed.