# Non-Hermitian band topology from momentum-dependent relaxation in two-dimensional metals with spiral magnetism

@inproceedings{Mitscherling2021NonHermitianBT, title={Non-Hermitian band topology from momentum-dependent relaxation in two-dimensional metals with spiral magnetism}, author={Johannes Mitscherling and Walter Metzner}, year={2021} }

We study the emergence of non-Hermitian band topology in a two-dimensional metal with planar spiral magnetism due to a momentum-dependent relaxation rate. A sufficiently strong momentum dependence of the relaxation rate leads to exceptional points in the Brillouin zone, where the Hamiltonian is non-diagonalizable. The exceptional points appear in pairs with opposite topological charges and are connected by arc-shaped branch cuts. We show that exceptional points inside hole and electron pockets… Expand

#### References

SHOWING 1-10 OF 27 REFERENCES

Non-Hermitian topology of spontaneous magnon decay

- Physics
- Physical Review B
- 2019

Spontaneous magnon decay is a generic feature of the magnetic excitations of anisotropic magnets and isotropic magnets with noncollinear order. In this Rapid Communication, we argue that the effect… Expand

Non-Hermitian perspective of the band structure in heavy-fermion systems

- Physics
- 2018

We analyze a two-dimensional Kondo lattice model with special emphasis on non-Hermitian properties of the single-particle spectrum, following a recent proposal by Kozii and Fu. Our analysis based on… Expand

Disorder-induced exceptional points and nodal lines in Dirac superconductors

- Physics
- Physical Review B
- 2019

We consider the effect of disorder on the spectrum of quasiparticles in the point-node and nodal-line superconductors. Due to the anisotropic dispersion of quasiparticles disorder scattering may… Expand

Symmetry-protected exceptional rings in two-dimensional correlated systems with chiral symmetry

- Physics
- Physical Review B
- 2019

Emergence of exceptional points in two dimensions is one of the remarkable phenomena in non-Hermitian systems. We here elucidate the impacts of symmetry on the non-Hermitian physics. Specifically, we… Expand

Disorder-driven exceptional lines and Fermi ribbons in tilted nodal-line semimetals

- Physics
- 2019

We consider the impact of disorder on the spectrum of three-dimensional nodal-line semimetals. We show that the combination of disorder and a tilted spectrum naturally leads to a non-Hermitian… Expand

Chiral-symmetry protected exceptional torus in correlated nodal-line semimetals

- Physics
- Physical Review B
- 2019

We analyze a diamond-lattice Hubbard model with the spatially modulated Hubbard interaction. Our dynamical mean-field analysis with special emphasis on non-Hermitian properties elucidates that the… Expand

Relationship between exceptional points and the Kondo effect in
f
-electron materials

- Physics
- 2020

We study the impact of nonhermiticity due to strong correlations in f-electron materials. One of the most remarkable phenomena occurring in nonhermitian systems is the emergence of exceptional points… Expand

Magnetic phases of the two-dimensional Hubbard model at low doping.

- Physics, Medicine
- Physical review. B, Condensed matter
- 1995

The spin-density-wave formalism is used and it is found that the equilibrium spin configuration of the 2D Hubbard model at low doping is noncoplanar, leading to a novel scenario of spin reorientation upon doping in Hubbard antiferromagnets. Expand

Slave-Boson Approach to Spiral Magnetic Order in the Hubbard Model

- Physics
- 1991

We show that for the Hubbard model on the square lattice a spiral magnetic state characterized by a wave vector Q = (π - δQx, π), where δQx increases with the concentration δ of holes in the… Expand

Nodal arc of disordered Dirac fermions and non-Hermitian band theory

- Physics
- Physical Review B
- 2019

We show that Dirac fermion systems in two dimensions generally exhibit disorder-induced nodal arc replacing the nodal point and tilted Dirac cone, provided that the two components of the Dirac… Expand