{
  "id": "1611.10123",
  "version": "v1",
  "published": "2016-11-30T12:30:38.000Z",
  "updated": "2016-11-30T12:30:38.000Z",
  "title": "Low-temperature thermometry enhanced by strong coupling",
  "authors": [
    "Luis A. Correa",
    "Martí Perarnau-Llobet",
    "Karen V. Hovhannisyan",
    "Senaida Hernández-Santana",
    "Mohammad Mehboudi",
    "Anna Sanpera"
  ],
  "comment": "6+7 pages, 4 figures",
  "categories": [
    "quant-ph",
    "cond-mat.stat-mech"
  ],
  "abstract": "We consider the problem of estimating the temperature $ T $ of a very cold equilibrium sample with an individual quantum probe. In particular, $ T $ is inferred from measurements performed on a single quantum harmonic probe strongly coupled to the sample under investigation. Due to the non-perturbative probe-sample interaction the stationary state of the former will not be thermal, in general. This turns out to be potentially advantageous for measuring low temperatures, as we show that: (i) The thermometric precision at low $ T $ can be significantly enhanced by strengthening the probe-sampling coupling, (ii) the variance of a suitable quadrature of our single-mode thermometer can yield temperature estimates with nearly minimal statistical uncertainty, and (iii) the spectral density of the probe-sample coupling may be engineered to further improve thermometric performance. These observations may find applications in practical nanoscale thermometry at low temperatures---a regime which is particularly relevant to quantum technologies.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2016-11-30T12:30:38.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "low-temperature thermometry",
      "strong coupling",
      "single quantum harmonic probe",
      "individual quantum probe",
      "cold equilibrium sample"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 7,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}