Simulating Exceptional Non-Hermitian Metals with Single-Photon Interferometry

• URL: http://arxiv.org/abs/2011.01884v2
• Date: Mon, 12 Jul 2021 08:51:15 GMT
• Title: Simulating Exceptional Non-Hermitian Metals with Single-Photon Interferometry
• Authors: Kunkun Wang, Lei Xiao, Jan Carl Budich, Wei Yi, Peng Xue
• Abstract summary: We experimentally simulate in a photonic setting non-Hermitian (NH) metals characterized by the topological properties of their nodal band structures. We focus on two distinct types of NH metals: two-dimensional systems with symmetry-protected ELs, and three-dimensional systems possessing symmetry-independent topological ELs in the form of knots.
• Score: 4.030017427802459
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: We experimentally simulate in a photonic setting non-Hermitian (NH) metals characterized by the topological properties of their nodal band structures. Implementing nonunitary time evolution in reciprocal space followed by interferometric measurements, we probe the complex eigenenergies of the corresponding NH Bloch Hamiltonians, and study in detail the topology of their exceptional lines (ELs), the NH counterpart of nodal lines in Hermitian systems. We focus on two distinct types of NH metals: two-dimensional systems with symmetry-protected ELs, and three-dimensional systems possessing symmetry-independent topological ELs in the form of knots. While both types feature open Fermi surfaces, we experimentally observe their distinctions by analyzing the impact of symmetry-breaking perturbations on the topology of ELs.

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