{
  "id": "1607.02428",
  "version": "v1",
  "published": "2016-07-08T15:52:05.000Z",
  "updated": "2016-07-08T15:52:05.000Z",
  "title": "0-$π$ phase-controllable $thermal$ Josephson junction",
  "authors": [
    "Antonio Fornieri",
    "Giuliano Timossi",
    "Pauli Virtanen",
    "Paolo Solinas",
    "Francesco Giazotto"
  ],
  "comment": "10 pages, 9 color figures",
  "categories": [
    "cond-mat.mes-hall"
  ],
  "abstract": "Two superconductors coupled by a weak link support an equilibrium Josephson electrical current which depends on the phase difference $\\varphi$ between the superconducting condensates [1]. Yet, when a temperature gradient is imposed across the junction, the Josephson effect manifests itself through a coherent component of the heat current that flows oppositely to the thermal gradient for $ \\varphi <\\pi/2$ [2-4]. The direction of both the Josephson charge and heat currents can be inverted by adding a $\\pi$ shift to $\\varphi$. In the static electrical case, this effect was obtained in a few systems, e.g. via a ferromagnetic coupling [5,6] or a non-equilibrium distribution in the weak link [7]. These structures opened new possibilities for superconducting quantum logic [6,8] and ultralow power superconducting computers [9]. Here, we report the first experimental realization of a thermal Josephson junction whose phase bias can be controlled from $0$ to $\\pi$. This is obtained thanks to a superconducting quantum interferometer that allows to fully control the direction of the coherent energy transfer through the junction [10]. This possibility, joined to the completely superconducting nature of our system, provides temperature modulations with unprecedented amplitude of $\\sim$ 100 mK and transfer coefficients exceeding 1 K per flux quantum at 25 mK. Then, this quantum structure represents a fundamental step towards the realization of caloritronic logic components, such as thermal transistors, switches and memory devices [10,11]. These elements, combined with heat interferometers [3,4,12] and diodes [13,14], would complete the thermal conversion of the most important phase-coherent electronic devices and benefit cryogenic microcircuits requiring energy management, such as quantum computing architectures and radiation sensors.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2016-07-08T15:52:05.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "josephson junction",
      "weak link",
      "cryogenic microcircuits requiring energy management",
      "benefit cryogenic microcircuits requiring energy",
      "important phase-coherent electronic devices"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 10,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}