# Non-Hermitian higher-order Weyl semimetals

@article{Ghorashi2021NonHermitianHW, title={Non-Hermitian higher-order Weyl semimetals}, author={Sayed Ali Akbar Ghorashi and Tianhe Li and Masatoshi Sato}, journal={Physical Review B}, year={2021} }

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…

## 5 Citations

Higher-Order Weyl-Exceptional-Ring Semimetals.

- MathematicsPhysical review letters
- 2021

For first-order topological semimetals, non-Hermitian perturbations can drive the Weyl nodes into Weyl exceptional rings having multiple topological structures and no Hermitian counterparts.…

Non-Hermitian Weyl semimetal and its Floquet engineering

- PhysicsPhysical Review B
- 2022

It is generally believed that non-Hermiticity can transform Weyl semimetals into Weyl-exceptional-ring semimetals. However, this belief is from the systems without skin eﬀect. We investigate the…

Always-Real-Eigenvalued Non-Hermitian Topological Systems

- Physics
- 2021

The effect of non-Hermiticity in band topology has sparked many discussions on non-Hermitian topological physics. It has long been known that non-Hermitian Hamiltonians can exhibit real energy…

Degeneracy and defectiveness in non-Hermitian systems with open boundary

- MathematicsPhysical Review B
- 2022

We develop a systematically general theory of one-dimensional (1D) non-Hermitian systems, elaborating the energy bands, the band degeneracy, and the defectiveness of eigenstates under open boundary…

Anomalous Transport Induced by Non-Hermitian Anomalous Berry Connection in Non-Hermitian Systems

- PhysicsChinese Physics Letters
- 2022

Non-Hermitian materials can exhibit not only exotic energy band structures but also an anomalous velocity induced by non-Hermitian anomalous Berry connection as predicted by the semiclassical…

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