{
  "annotation_id": "f89e0b5b-4174-47f9-95af-e82560a985b3",
  "date_created": "2026-03-02T18:01:59.933000Z",
  "date_modified": "2026-03-02T18:01:59.933000Z",
  "file_hash": "c333cbe3a9c84b134be3c7fb49d336736300c663635160affb5b47244f9eac06",
  "private": false,
  "record": {
    "abstract": "Extending the scheme developed for a single mode of the electromagnetic field\nin the preceding paper ``Structure of multiphoton quantum optics. I. Canonical\nformalism and homodyne squeezed states\u0027\u0027, we introduce two-mode nonlinear\ncanonical transformations depending on two heterodyne mixing angles. They are\ndefined in terms of hermitian nonlinear functions that realize heterodyne\nsuperpositions of conjugate quadratures of bipartite systems. The canonical\ntransformations diagonalize a class of Hamiltonians describing non degenerate\nand degenerate multiphoton processes. We determine the coherent states\nassociated to the canonical transformations, which generalize the non\ndegenerate two--photon squeezed states. Such heterodyne multiphoton squeezed\nare defined as the simultaneous eigenstates of the transformed, coupled\nannihilation operators. They are generated by nonlinear unitary evolutions\nacting on two-mode squeezed states. They are non Gaussian, highly non\nclassical, entangled states. For a quadratic nonlinearity the heterodyne\nmultiphoton squeezed states define two--mode cubic phase states. The\nstatistical properties of these states can be widely adjusted by tuning the\nheterodyne mixing angles, the phases of the nonlinear couplings, as well as the\nstrength of the nonlinearity. For quadratic nonlinearity, we study the\nhigher-order contributions to the susceptibility in nonlinear media and we\nsuggest possible experimental realizations of multiphoton conversion processes\ngenerating the cubic-phase heterodyne squeezed states.",
    "arxiv_id": "quant-ph/0308094",
    "authors": [
      "Fabio Dell\u0027Anno",
      "Silvio De Siena",
      "Fabrizio Illuminati"
    ],
    "categories": [
      "quant-ph",
      "cond-mat",
      "hep-th",
      "math-ph",
      "math.MP",
      "physics.optics"
    ],
    "doi": "10.1103/PhysRevA.69.033813",
    "journal_ref": "Phys.Rev. A69 (2004) 033813",
    "title": "Structure of multiphoton quantum optics. II. Bipartite systems, physical   processes, and heterodyne squeezed states",
    "url": "https://arxiv.org/abs/quant-ph/0308094"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "f8ab6158-c4f1-40a9-94ff-d57dc3a40c8b",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}