Experimental demonstration of a unidirectional reflectionless parity-time metamaterial at optical frequencies.

@article{Feng2013ExperimentalDO,
  title={Experimental demonstration of a unidirectional reflectionless parity-time metamaterial at optical frequencies.},
  author={Liang Feng and Ye-Long Xu and William S. Fegadolli and Ming-Hui Lu and Jos{\'e} Edimar Barbosa Oliveira and Vilson R Almeida and Yan-Feng Chen and Axel Scherer},
  journal={Nature materials},
  year={2013},
  volume={12 2},
  pages={
          108-13
        }
}
Invisibility by metamaterials is of great interest, where optical properties are manipulated in the real permittivity-permeability plane. However, the most effective approach to achieving invisibility in various military applications is to absorb the electromagnetic waves emitted from radar to minimize the corresponding reflection and scattering, such that no signal gets bounced back. Here, we show the experimental realization of chip-scale unidirectional reflectionless optical metamaterials… 
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