{
  "id": "2001.04969",
  "version": "v1",
  "published": "2020-01-14T18:57:18.000Z",
  "updated": "2020-01-14T18:57:18.000Z",
  "title": "Non-Hermitian band topology in active and dissipative mechanical metamaterials",
  "authors": [
    "Colin Scheibner",
    "William T. M. Irvine",
    "Vincenzo Vitelli"
  ],
  "comment": "Four figures with supplementary information",
  "categories": [
    "cond-mat.soft"
  ],
  "abstract": "Networks of masses with transverse spring-like interactions provide a simple model of solids with energetic gain and loss. In this Letter, we study the non-Hermitian band topology of this model, which applies not only to active solids but also to gyroscopic metamaterials with dissipation. We examine a family of lattices in which topologically charged bands arise as activity (dissipation) is increased (decreased). The topological transition proceeds by a mechanism absent in Hermitian systems: Dirac cones spread out into exceptional rings rather than acquiring a gap. Above the transition, we observe chiral edge modes with a penetration depth that does not diverge even when the band gap closes.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2020-01-14T18:57:18.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "non-hermitian band topology",
      "dissipative mechanical metamaterials",
      "band gap closes",
      "chiral edge modes",
      "dirac cones spread"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 0,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}