{
  "annotation_id": "22f5edc3-73b5-435e-84f0-9743ffcec6c6",
  "date_created": "2026-03-02T18:00:39.046000Z",
  "date_modified": "2026-03-02T18:00:39.046000Z",
  "file_hash": "35bd128c9c7b739c9a5c560f5e0c77725f4ce96d38c7e97cd1ce346605380f72",
  "private": false,
  "record": {
    "abstract": "We study electromagnetic wave propagation in mediums in which the effective\nrelative permittivity and the effective relative permeability are allowed to\ntake any value in the upper half of the complex plane. A general condition is\nderived for the phase velocity to be oppositely directed to the power flow.\nThat extends the recently studied case of propagation in mediums for which the\nrelative permittivity and relative permeability are both simultaneously\nnegative, to include dissipation as well. An illustrative case study\ndemonstrates that in general the spectrum divides into five distinct regions.",
    "arxiv_id": "physics/0204067",
    "authors": [
      "M. W. McCall",
      "A. Lakhtakia",
      "W. S. Weiglhofer"
    ],
    "categories": [
      "physics.class-ph",
      "physics.gen-ph"
    ],
    "doi": "10.1088/0143-0807/23/3/314",
    "journal_ref": "European Journal of Physics, Vol. 23, no. 3, pp. 353-359 (2002)",
    "title": "The negative index of refraction demystified",
    "url": "https://arxiv.org/abs/physics/0204067"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "c7af12d1-1538-4b33-b735-03364fb9304b",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}