An exceptional surface and its topology

• URL: http://arxiv.org/abs/2501.04317v1
• Date: Wed, 08 Jan 2025 07:28:39 GMT
• Title: An exceptional surface and its topology
• Authors: Shou-Bang Yang, Pei-Rong Han, Wen Ning, Fan Wu, Zhen-Biao Yang, Shi-Biao Zheng,
• Abstract summary: Non-Hermitian (NH) systems can display exceptional topological defects without Hermitian counterparts. We investigate the topology for the singularities in an NH three-dimensional system. Our results pave the way for investigations of exceptional topology associated with topological defects with more than one dimension.
• Score: 2.2706551270477613
• License:
• Abstract: Non-Hermitian (NH) systems can display exceptional topological defects without Hermitian counterparts, exemplified by exceptional rings in NH two-dimensional systems. However, exceptional topological features associated with higher-dimension topological defects remain unexplored yet. We here investigate the topology for the singularities in an NH three-dimensional system. We find that the three-order singularities in the parameter space form an exceptional surface (ES), on which all the three eigenstates and eigenenergies coalesce. Such an ES corresponds to a two-dimensional extension of a point-like synthetic tensor monopole. We quantify its topology with the Dixmier-Douady invariant, which measures the quantized flux associated with the synthetic tensor field. We further propose an experimentally feasible scheme for engineering such an NH model. Our results pave the way for investigations of exceptional topology associated with topological defects with more than one dimension.

Related papers

• Topological Order in the Spectral Riemann Surfaces of Non-Hermitian Systems [44.99833362998488]
  We show topologically ordered states in the complex-valued spectra of non-Hermitian systems. These arise when the distinctive exceptional points in the energy surfaces of such models are annihilated. We illustrate the characteristics of the topologically protected states in a non-Hermitian two-band model.
  arXiv  Detail & Related papers  (2024-10-24T10:16:47Z)
• A Noisy Approach to Intrinsically Mixed-State Topological Order [0.0]
  We show that the resulting mixed-state can display intrinsically mixed-state topological order (imTO) We find that gauging out anyons generically results in imTO, with the decohered mixed-state strongly symmetric under certain anomalous 1-form symmetries.
  arXiv  Detail & Related papers  (2024-03-20T18:00:01Z)
• Measuring topological invariants for higher-order exceptional points in quantum three-mode systems [1.9334835720031431]
  Experimental characterizations of exceptional topological invariants have been restricted to second-order EPs in classical or semiclassical systems. We here propose an NH multi-mode system with higher-order EPs, each of which is underlain by a multifold-degenerate multipartite entangled eigenstate. Our results extend research of exceptional topology to fully quantum-mechanical models with multipartite entangled eigenstates.
  arXiv  Detail & Related papers  (2024-02-05T09:51:01Z)
• Mixed-State Entanglement Measures in Topological Order [0.685316573653194]
  We study the entanglement in topologically ordered states between two arbitrary spatial regions. While the field-theoretic results are expected to be topological and universal, the lattice results contain nontopological/nonuniversal terms as well.
  arXiv  Detail & Related papers  (2023-01-19T17:59:50Z)
• Restoration of the non-Hermitian bulk-boundary correspondence via topological amplification [0.0]
  Non-Hermitian (NH) lattice Hamiltonians display a unique kind of energy gap and extreme sensitivity to boundary conditions. Due to the NH skin effect, the separation between edge and bulk states is blurred. We restore the bulk-boundary correspondence for the most paradigmatic class of NH Hamiltonians.
  arXiv  Detail & Related papers  (2022-07-25T18:00:03Z)
• Non-Gaussian superradiant transition via three-body ultrastrong coupling [62.997667081978825]
  We introduce a class of quantum optical Hamiltonian characterized by three-body couplings. We propose a circuit-QED scheme based on state-of-the-art technology that implements the considered model.
  arXiv  Detail & Related papers  (2022-04-07T15:39:21Z)
• Non-Hermitian $C_{NH} = 2$ Chern insulator protected by generalized rotational symmetry [85.36456486475119]
  A non-Hermitian system is protected by the generalized rotational symmetry $H+=UHU+$ of the system. Our finding paves the way towards novel non-Hermitian topological systems characterized by large values of topological invariants.
  arXiv  Detail & Related papers  (2021-11-24T15:50:22Z)
• Simulating Exceptional Non-Hermitian Metals with Single-Photon Interferometry [4.030017427802459]
  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.
  arXiv  Detail & Related papers  (2020-11-03T18:00:49Z)
• Quantum anomalous Hall phase in synthetic bilayers via twistless twistronics [58.720142291102135]
  We propose quantum simulators of "twistronic-like" physics based on ultracold atoms and syntheticdimensions. We show that our system exhibits topologicalband structures under appropriate conditions.
  arXiv  Detail & Related papers  (2020-08-06T19:58:05Z)
• Dynamical solitons and boson fractionalization in cold-atom topological insulators [110.83289076967895]
  We study the $mathbbZ$ Bose-Hubbard model at incommensurate densities. We show how defects in the $mathbbZ$ field can appear in the ground state, connecting different sectors. Using a pumping argument, we show that it survives also for finite interactions.
  arXiv  Detail & Related papers  (2020-03-24T17:31:34Z)
• Probing chiral edge dynamics and bulk topology of a synthetic Hall system [52.77024349608834]
  Quantum Hall systems are characterized by the quantization of the Hall conductance -- a bulk property rooted in the topological structure of the underlying quantum states. Here, we realize a quantum Hall system using ultracold dysprosium atoms, in a two-dimensional geometry formed by one spatial dimension. We demonstrate that the large number of magnetic sublevels leads to distinct bulk and edge behaviors.
  arXiv  Detail & Related papers  (2020-01-06T16:59:08Z)

This list is automatically generated from the titles and abstracts of the papers in this site.

This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.