{
  "id": "quant-ph/0601085",
  "version": "v1",
  "published": "2006-01-12T23:34:55.000Z",
  "updated": "2006-01-12T23:34:55.000Z",
  "title": "The meaning of group delay in barrier tunneling: A re-examination of superluminal group velocities",
  "authors": [
    "Herbert G. Winful"
  ],
  "comment": "33 pages, 4 figures",
  "journal": "New J. Phys. 8, 101 (2006) http://stacks.iop.org/1367-2630/8/101",
  "doi": "10.1088/1367-2630/8/6/101",
  "categories": [
    "quant-ph",
    "physics.optics"
  ],
  "abstract": "We show that the group delay in tunneling is not a traversal time but a lifetime of stored energy or stored probability escaping through both ends of the barrier. Because it is a lifetime associated with both forward (transmitted) and backward (reflected) fluxes, it cannot be used to define a group velocity for forward transit in cases where a wavepacket is mostly reflected. For photonic tunneling barriers the group delay is identical to the dwell time which is also a property of an entire wave function with reflected and transmitted components. Theoretical predictions and experimental reports of superluminal group velocities in barrier tunneling are re-interpreted.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2006-01-12T23:34:55.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "group velocity",
      "superluminal group velocities",
      "group delay",
      "barrier tunneling",
      "re-examination"
    ],
    "tags": [
      "journal article"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 33,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}