THREE-DIMENSIONAL THERMAL CLOAK WITH HOMOGENEOUS AND NONSINGULAR CONDUCTIVE MATERIALS

Most three-dimensional omnidirectional cloaks proposed to date (using optics, electromagnetics, and acoustics) are not easily realized, as they possess inhomogeneous and singular parameters imposed by the transformation-optic method. In this study, we theoretically demonstrate that a thermodynamic spherical cloak with homogeneous and finite conductivity and employing only naturally available conductive materials may be achieved. More interestingly, the thermal localization inside the coating layer can be tuned by anisotropy, which may lead to nearly perfect functionality in an incomplete cloak. The practical realization of such a homogeneous thermal cloak by using two naturally occurring materials has been suggested, which provides an unprecedentedly plausible way to flexibly achieve a thermal cloak and manipulate heat flow. Numerical experiments validate the excellent performance of the proposed homogeneous cloak functions.