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On some constraints that limit the design of an invisibility cloak

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 نشر من قبل Huanyang Chen
 تاريخ النشر 2007
  مجال البحث فيزياء
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Using the idea of transformation medium, a cloak can be designed to make a domain invisible for one target frequency. In this article, we examine the possibility to extend the bandwidth of such a cloak. We obtained a constraint of the band width, which is summarized as a simple inequality that states that limits the bandwidth of operation. The constraint originates from causality requirements. We suggest a simple strategy that can get around the constraint.



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