{
  "annotation_id": "2b9dba9a-7544-4adc-8e47-462965696a88",
  "date_created": "2026-03-02T18:01:56.379000Z",
  "date_modified": "2026-03-02T18:01:56.379000Z",
  "file_hash": "6d4d64e5faf731b509f5d6dd589f040279f832484b263a9e216551b5a26d7d18",
  "private": false,
  "record": {
    "abstract": "A photon echo experiment has been performed using accumulated highly\nattenuated laser pulses. We show experimentally that the photon echo process\ncan be performed with, on the average, less than one photon in each pair of\nexcitation pulses. The results support an interpretation where this non-linear\nprocess can be performed with, on the average, less than one photon shared\nbetween two of the optical fields involved in the degenerate four-wave mixing\nprocess. Further, we argue that the experiment can be interpreted as a form of\ndelayed self-interference for photon wave packets that do not overlap in both\nspace and time.",
    "arxiv_id": "quant-ph/0301157",
    "authors": [
      "Nicklas Ohlsson",
      "Mattias Nilsson",
      "Stefan Kroll"
    ],
    "categories": [
      "quant-ph"
    ],
    "doi": "10.1103/PhysRevA.68.063812",
    "journal_ref": "Phys. Rev. A 68, 063812 (2003)",
    "title": "Experimental investigation of delayed self-interference for single   photons",
    "url": "https://arxiv.org/abs/quant-ph/0301157"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "b46b05ec-8a2e-42eb-8a52-14d5334b9de9",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}