Examining the limitations of ideal cylindrical cloaks through dispersive finite-difference time-domain simulations

In this paper the limitations of the cloak´s transient response were studied. It can be concluded that the ideal cylindrical cloak, even though it is supposed to be ldquoidealrdquo, has some drawbacks. The highly dispersive nature of the device is the main reason for these limitations, which are directly affecting its performance. It is deduced that the cloak is very narrowband, ideally operates correctly only at one frequency. In order to avoid these restraints, broadband active metamaterials have to be designed or, alternative, novel non-dispersive cloak designs have to be conceived.