Sensitiveness of cloaking performance on moderate material parameter violation

A coordinate transformation approach dictates inhomogeneous and anisotropic medium in cloaks´ design. In this paper, the sensitiveness of different cloaking schemes based approximate cloaks, in which the EM parameters are limited to a range more plausible to realize, is investigated. When devising the cloak using dispersive lossy metamaterials, the unavoidable deviation in material parameters degraded the cloak´s performance significantly, especially in terms of bandwidth. Numerical experiments show that the imperfect cloak under moderate compression presents low anisotropy and is a candidate scheme more insusceptible to moderate changes in EM parameters.