Non-Hermitian higher-order Weyl semimetals

  title={Non-Hermitian higher-order Weyl semimetals},
  author={Sayed Ali Akbar Ghorashi and Tianhe Li and Masatoshi Sato},
  journal={Physical Review B},
We study non-Hermitian higher-order Weyl semimetals (NHHOWSMs) possessing real spectra and having inversion I (I-NHHOWSM) or time-reversal symmetry T (T -NHHOWSM). When the reality of bulk spectra is lost, the NHHOWSMs exhibit various configurations of surface Fermi Arcs (FAs) and Exceptional Fermi Rings (EFRs), providing a setup to investigate them on an equal footing. The EFRs only appear in the region between 2nd-order WNs. We also discover Weyl nodes originating from non-Hermicity, called… 

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