Topological Defect Engineering and PT Symmetry in Non-Hermitian Electrical Circuits.

  title={Topological Defect Engineering and PT Symmetry in Non-Hermitian Electrical Circuits.},
  author={Alexander Stegmaier and Stefan Imhof and Tobias Helbig and Tobias Hofmann and Ching Hua Lee and Mark Kremer and Alexander Fritzsche and Thorsten Feichtner and Sebastian Klembt and S. Hofling and Igor Boettcher and Ion Cosma Fulga and Oliver G. Schmidt and Martin Greiter and Tobias Kie{\ss}ling and Alexander Szameit and Ronny Thomale},
  journal={Physical review letters},
  volume={126 21},
We employ electric circuit networks to study topological states of matter in non-Hermitian systems enriched by parity-time symmetry PT and chiral symmetry anti-PT (APT). The topological structure manifests itself in the complex admittance bands which yields excellent measurability and signal to noise ratio. We analyze the impact of PT-symmetric gain and loss on localized edge and defect states in a non-Hermitian Su-Schrieffer-Heeger (SSH) circuit. We realize all three symmetry phases of the… 

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