{
  "annotation_id": "29f91b7f-f69f-4c14-86d2-1639b1392728",
  "date_created": "2026-03-02T18:00:46.919000Z",
  "date_modified": "2026-03-02T18:00:46.919000Z",
  "file_hash": "49cf9a7b89dc418f9d5bcb076f57056b8439705cfdeda10ac2eb49db6c9a0c60",
  "private": false,
  "record": {
    "abstract": "The collinear eZe configuration of helium, with the electrons on opposite\nsides of the nucleus, is studied in the presence of an external electromagnetic\n(laser or microwave) field. We show that the classically unstable \"asymmetric\nstretch\" orbit, on which doubly excited intrashell states of helium with\nmaximum interelectronic angle are anchored, can be stabilized by means of a\nresonant driving where the frequency of the electromagnetic field equals the\nfrequency of Kepler-like oscillations along the orbit. A static magnetic field,\noriented parallel to the oscillating electric field of the driving, can be used\nto enforce the stability of the configuration with respect to deviations from\ncollinearity. Quantum Floquet calculations within a collinear model of the\ndriven two-electron atom reveal the existence of nondispersive wave packets\nlocalized on the stabilized asymmetric stretch orbit, for double excitations\ncorresponding to principal quantum numbers of the order of N \u003e 10.",
    "arxiv_id": "physics/0307112",
    "authors": [
      "Peter Schlagheck",
      "Detlef Pingel",
      "Peter Schmelcher"
    ],
    "categories": [
      "physics.atom-ph"
    ],
    "doi": "10.1103/PhysRevA.68.053410",
    "title": "Collinear helium under periodic driving: stabilization of the asymmetric   stretch orbit",
    "url": "https://arxiv.org/abs/physics/0307112"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "24e3d8ec-9ec3-4107-b808-ce030c3648f4",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}