A GL Double Layer EM Cloaks In Broad Frequency Band And Reciprocal Law

GL Geophysical Laboratory, USA(Dated: February 23, 2010)In this paper, we propose a novel GL double layer EM cloak in the broad frequency band. Inshort, we call it as GLWF double EM cloak. The GLWF double layer cloak (GLWF cloak) consistsof two sphere annular layers, two type cloak materials are proposed and installed in its each layer,respectively. The outer layer of the GL cloak has the invisible function in broad frequency band,while its inner layer has the fully absorption and rapid delay function. The outer layer cloaksthe Local concealment from the Global exterior EM field; The inner layer cloaks the Global freespace region from the Local field excited inside the concealment. The GLWF double layer cloakovercomes the following difficulties of the single layer PS cloak. (1) There exists no EM wavefieldcan be excited inside the concealment of the PS cloak, the concealment of the PS cloak is blind.Our GL double layer cloak recovered that the EM wave field can be excited inside the concealmentof the GL double layer cloak. (2) There is exceeding light speed physical violation in PS cloak, itsinvisibility only in very narrow frequency band. Our GLWF double layer cloak corrects the violation.(3) The reciprocal law is satisfied in our GL double cloak media. However, the PS cloak damagedthe reciprocal law.. The simulations and comparisons of the EM wave field propagation through theGLWF double cloak, GL double cloak and GL double layer with PS outer layer are presented toshow the advantages of the GLWF double layer EM cloak The GL double layer cloaks are proposedby our GL EM modeling and inversion. The 3D GL EM modeling simulations for the double layercloak are presented. The copyright and patent of the GLWF double layer cloak materials and GLEM modeling and inversion in this paper are reserved by authors in GL Geophysical Laboratory.