{
  "id": "1802.03845",
  "version": "v1",
  "published": "2018-02-12T00:16:36.000Z",
  "updated": "2018-02-12T00:16:36.000Z",
  "title": "Improved sensitivity to magnetic fields by rotation of quantum sensors",
  "authors": [
    "A. A. Wood",
    "A. G. Aeppli",
    "E. Lilette",
    "Y. Y. Fein",
    "A. Stacey",
    "L. C. L. Hollenberg",
    "R. E. Scholten",
    "A. M. Martin"
  ],
  "comment": "7 pages, 4 figures",
  "categories": [
    "quant-ph"
  ],
  "abstract": "Magnetic sensors are typically much more sensitive to oscillating (AC) magnetic fields than static (DC) fields, due to the presence of more noise at lower frequency, typically scaling with a $1/f$ dependence. For quantum magnetometers, this characteristic noise is reflected in the ensemble dephasing time $T_2^*$, the relevant sensing time for a DC field, being much lower than the spin coherence time $T_2$, which determines the sensitivity to AC fields. Here, we demonstrate measurement of DC magnetic fields using a physically rotating ensemble of nitrogen-vacancy centres at a precision limited by the electron spin coherence time, $T_2$. We rotate the host diamond with a period comparable to $T_2$, such that the angle between the NV axis and the magnetic field to be detected changes as a function of time, upconverting the static magnetic field to an oscillating field in the physically rotating frame. Using spin-echo interferometry, we observe an order of magnitude improvement in DC magnetometer response compared to a conventional Ramsey experiments. Enhancements to our scheme could realise DC sensitivities equivalent to demonstrated AC magnetic field sensitivities with NV centres.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2018-02-12T00:16:36.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "sensitivity",
      "quantum sensors",
      "demonstrated ac magnetic field sensitivities",
      "electron spin coherence time",
      "realise dc sensitivities equivalent"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 7,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}