English

Non-Hermitian exceptional physics in RP^2 hyperbolic media

Optics 2025-05-09 v1

Abstract

Conventional momentum space provides an orientable base space of a torus for topological classifications based on band theory. Here, we introduce a non-orientable momentum space isomorphic to the real projective plane RP^2 within the low-symmetry media. We show that the local band fluidity can be characterized by an expanded dihedral group with non-Abelian properties, while the global band fluidity offers a versatile platform to explore the evolution of non-Hermitian exceptional manifolds, including order-1, higher-order, hybrid exceptional manifolds, diabolic points and even bound states in the continuum. Furthermore, the non-orientable momentum space can pave the way for exploring the emergence of phenomena for exceptional manifolds.

Keywords

Cite

@article{arxiv.2505.04932,
  title  = {Non-Hermitian exceptional physics in RP^2 hyperbolic media},
  author = {Shengyu Hu and Zhiwei Guo and Wenwei Liu and Shuqi Chen and Hong Chen},
  journal= {arXiv preprint arXiv:2505.04932},
  year   = {2025}
}
R2 v1 2026-06-28T23:25:17.107Z