{
  "annotation_id": "161f317b-1a57-467a-afc2-69cd2c1ed259",
  "date_created": "2026-03-02T18:02:16.739000Z",
  "date_modified": "2026-03-02T18:02:16.739000Z",
  "file_hash": "389f4712444b91419fc5df3dc1472e12de862e8cc5e87cb13f6bf4b839788b65",
  "private": false,
  "record": {
    "abstract": "We present the first measurement of squeezed-state entanglement between the\ntwin beams produced in an Optical Parametric Oscillator (OPO) operating above\nthreshold. Besides the usual squeezing in the intensity difference between the\ntwin beams, we have measured squeezing in the sum of phase quadratures. Our\nscheme enables us to measure such phase anti-correlations between fields of\ndifferent frequencies. In the present measurements, wavelengths differ by ~1\nnm. Entanglement is demonstrated according to the Duan et al. criterion [Phys.\nRev. Lett. 84, 2722 (2000)] $\\Delta^2\\hat{p}_- +\\Delta^2\\hat{q}_+=1.47(2)\u003c2$.\nThis experiment opens the way for new potential applications such as the\ntransfer of quantum information between different parts of the electromagnetic\nspectrum.",
    "arxiv_id": "quant-ph/0506139",
    "authors": [
      "A. S. Villar",
      "L. S. Cruz",
      "K. N. Cassemiro",
      "M. Martinelli",
      "P. Nussenzveig"
    ],
    "categories": [
      "quant-ph"
    ],
    "doi": "10.1103/PhysRevLett.95.243603",
    "title": "Generation of Bright Two-Color Continuous Variable Entanglement",
    "url": "https://arxiv.org/abs/quant-ph/0506139"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "d81fcffe-6466-41a6-80d4-2663d6a1cf59",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}