{
  "id": "1510.03981",
  "version": "v1",
  "published": "2015-10-14T07:21:51.000Z",
  "updated": "2015-10-14T07:21:51.000Z",
  "title": "Observation of quantum-limited heat conduction over macroscopic distances",
  "authors": [
    "Matti Partanen",
    "Kuan Yen Tan",
    "Joonas Govenius",
    "Russell E. Lake",
    "Miika K. Mäkelä",
    "Tuomo Tanttu",
    "Mikko Möttönen"
  ],
  "comment": "10 pages, 6 figures",
  "categories": [
    "cond-mat.mes-hall"
  ],
  "abstract": "The emerging quantum technological apparatuses [1,2], such as the quantum computer [3-5], call for extreme performance in thermal engineering at the nanoscale [6]. Importantly, quantum mechanics sets a fundamental upper limit for the flow of information and heat, which is quantified by the quantum of thermal conductance [7,8]. The physics of this kind of quantum-limited heat conduction has been experimentally studied for lattice vibrations, or phonons [9], for electromagnetic interactions [10], and for electrons [11]. However, the short distance between the heat-exchanging bodies in the previous experiments hinders the applicability of these systems in quantum technology. Here, we present experimental observations of quantum-limited heat conduction over macroscopic distances extending to a metre. We achieved this striking improvement of four orders of magnitude in the distance by utilizing microwave photons travelling in superconducting transmission lines. Thus it seems that quantum-limited heat conduction has no fundamental restriction in its distance. This work lays the foundation for the integration of normal-metal components into superconducting transmission lines, and hence provides an important tool for circuit quantum electrodynamics [12-14], which is the basis of the emerging superconducting quantum computer [15]. In particular, our results demonstrate that cooling of nanoelectronic devices can be carried out remotely with the help of a far-away engineered heat sink. In addition, quantum-limited heat conduction plays an important role in the contemporary studies of thermodynamics such as fluctuation relations and Maxwell's demon [16,17]. Here, the long distance provided by our results may, for example, lead to an ultimate efficiency of mesoscopic heat engines with promising practical applications [18].",
  "revisions": [
    {
      "version": "v1",
      "updated": "2015-10-14T07:21:51.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "macroscopic distances",
      "superconducting transmission lines",
      "observation",
      "quantum computer",
      "fundamental upper limit"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 10,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}