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A route to quasi-perfect invisibility cylindrical cloaks without extreme values in the parameters

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 نشر من قبل Hongsheng Chen
 تاريخ النشر 2008
  مجال البحث فيزياء
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The method of coordinate transformation offers a way to realize perfect cloaks, but provides less ability to characterize the performance of a multilayered cloak in practice. Here, we propose an analytical model to predict the performance of a multilayered cylindrical cloak, based on which, the cloak in practice can be optimized to diminish the intrinsic scatterings caused by discretization and simplification. Extremely low scattering or quasi-perfect invisibility can be achieved with only a few layers of anisotropic metamaterials without following the transformation method. Meanwhile, the permittivity and permeability parameters of the layers are relatively small, which is a remarkable advantage of our approach.



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