{
  "id": "2207.05326",
  "version": "v1",
  "published": "2022-07-12T05:46:12.000Z",
  "updated": "2022-07-12T05:46:12.000Z",
  "title": "Multitude of exceptional points in van der Waals bilayers",
  "authors": [
    "Xin Li",
    "Kuangyin Deng",
    "Benedetta Flebus"
  ],
  "categories": [
    "cond-mat.mes-hall"
  ],
  "abstract": "Several works have recently addressed the emergence of exceptional points (EPs), i.e., spectral singularities of non-Hermitian Hamiltonians, in the long-wavelength dynamics of coupled magnetic systems. Here, by focusing on the driven magnetization dynamics of a van der Waals ferromagnetic bilayer, we show that exceptional points can appear over extended portions of the first Brillouin zone as well. Furthermore, we demonstrate that the effective non-Hermitian magnon Hamiltonian, whose eigenvalues are purely real or come in complex-conjugate pairs, respects an unusual wavevector-dependent pseudo-Hermiticity. Finally, for both armchair and zigzag nanoribbon geometries, we discuss both the complex and purely real spectra of the topological edge states and their experimental implications.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2022-07-12T05:46:12.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "van der waals bilayers",
      "exceptional points",
      "van der waals ferromagnetic bilayer",
      "zigzag nanoribbon geometries",
      "unusual wavevector-dependent pseudo-hermiticity"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 0,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}