{
  "id": "2212.08237",
  "version": "v1",
  "published": "2022-12-16T02:10:20.000Z",
  "updated": "2022-12-16T02:10:20.000Z",
  "title": "Quantum sensing of temperature close to absolute zero in a Bose-Einstein condensate",
  "authors": [
    "Ji-Bing Yuan",
    "Bo Zhang",
    "Ya-Ju Song",
    "Shi-Qing Tang",
    "Xin-Wen Wang",
    "Le-Man Kuang"
  ],
  "comment": "9 pages,9 figures",
  "categories": [
    "quant-ph"
  ],
  "abstract": "We propose a theoretical scheme for quantum sensing of temperature close to absolute zero in a quasi-one-dimensional Bose-Einstein condensate (BEC). In our scheme, a single-atom impurity qubit is used as a temper-ature sensor. We investigate the sensitivity of the single-atom sensor in estimating the temperature of the BEC. We demonstrate that the sensitivity of the temperature sensor can saturate the quantum Cramer-Rao bound by means of measuring quantum coherence of the probe qubit. We study the temperature sensing performance by the use of quantum signal-to-noise ratio (QSNR). It is indicated that there is an optimal encoding time that the QSNR can reach its maximum in the full-temperature regime. In particular, we find that the QSNR reaches a finite upper bound in the weak coupling regime even when the temperature is close to absolute zero, which implies that the sensing-error-divergence problem is avoided in our scheme. Our work opens a way for quantum sensing of temperature close to absolute zero in the BEC.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2022-12-16T02:10:20.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "absolute zero",
      "temperature close",
      "quantum sensing",
      "quasi-one-dimensional bose-einstein condensate",
      "quantum signal-to-noise ratio"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 9,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}