Observation of an exceptional point in a non-Hermitian metasurface

@article{Park2020ObservationOA,
  title={Observation of an exceptional point in a non-Hermitian metasurface},
  author={Sang Hyun Park and Sung-Gyu Lee and Soojeong Baek and Taewoo Ha and Sanghyub Lee and Bumki Min and Shuang Zhang and Mark Lawrence and Teun-Teun Kim},
  journal={Nanophotonics},
  year={2020},
  volume={9},
  pages={1031 - 1039}
}
Abstract Exceptional points (EPs), also known as non-Hermitian degeneracies, have been observed in parity-time symmetric metasurfaces as parity-time symmetry breaking points. However, the parity-time symmetry condition puts constraints on the metasurface parameter space, excluding the full examination of unique properties that stem from an EP. Here, we thus design a general non-Hermitian metasurface with a unit cell containing two orthogonally oriented split-ring resonators (SRRs) with… 

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