Discriminant indicators with generalized inversion symmetry

We propose indicators of the discriminant for systems with generalized inversion symmetry which are computed from data only at high-symmetry points in the Brillouin zone. Our approach captures the exceptional points and their symmetry-protected variants without ambiguity arising from the reference energy, which is an advantage over the previously known indicators for non-Hermitian systems. As demonstrations, we systematically analyze 3x3 Hamiltonians where the proper choice of the reference energy is not obvious.

Automated summary

This paper proposes indicators for the discriminant of systems with generalized inversion symmetry, which can be computed from data at high-symmetry points in the Brillouin zone. The approach captures exceptional points and their symmetry-protected variants without ambiguity caused by the reference energy, which is an advantage compared to previously known indicators for non-Hermitian systems. As demonstrations, the authors systematically analyze 3x3 Hamiltonians where the proper choice of the reference energy is not obvious.