{
  "id": "2112.01899",
  "version": "v2",
  "published": "2021-12-03T13:27:43.000Z",
  "updated": "2022-05-03T15:20:13.000Z",
  "title": "Long Spin Coherence Times of Nitrogen Vacancy Centres in Milled Nanodiamonds",
  "authors": [
    "B. D. Wood",
    "G. A. Stimpson",
    "J. E. March",
    "Y. N. D. Lekhai",
    "C. J. Stephen",
    "B. L. Green",
    "A. C. Frangeskou",
    "L. Ginés",
    "S. Mandal",
    "O. A. Williams",
    "G. W. Morley"
  ],
  "comment": "Vresion 1: 13 pages, 7 figures. Standalone paper containing the nanodiamond spin coherence time results that first appeared in the pre-print \"Matter and spin superposition in vacuum experiment (MASSIVE)\" arXiv:2105.02105v1, with additional details added. Version 2: 11 pages, 7 figures. Grammar edits and reformatting to match published version",
  "journal": "Physical Review B 105, 205401 (2022)",
  "doi": "10.1103/PhysRevB.105.205401",
  "categories": [
    "cond-mat.mes-hall",
    "physics.optics",
    "quant-ph"
  ],
  "abstract": "Nanodiamonds containing negatively charged nitrogen vacancy centres (${\\text{NV}}^{-}$) have applications as localized sensors in biological material and have been proposed as a platform to probe the macroscopic limits of spatial superposition and the quantum nature of gravity. A key requirement for these applications is to obtain nanodiamonds containing ${\\text{NV}}^{-}$ with long spin coherence times. Using milling to fabricate nanodiamonds processes the full 3D volume of the bulk material at once, unlike etching, but has, up to now, limited ${\\text{NV}}^{-}$ spin coherence times. Here, we use natural isotopic abundance nanodiamonds produced by ${\\text{Si}}_{3}{\\text{N}}_{4}$ ball milling of bulk diamond grown by chemical vapour deposition with an average single substitutional nitrogen concentration of $121 ~\\text{ppb}$. We show that the electron spin coherence times of ${\\text{NV}}^{-}$ centres in these nanodiamonds can exceed $400 ~\\mu\\text{s}$ at room temperature with dynamical decoupling. Scanning electron microscopy provides images of the specific nanodiamonds containing ${\\text{NV}}^{-}$ for which a spin coherence time was measured.",
  "revisions": [
    {
      "version": "v2",
      "updated": "2022-05-03T15:20:13.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "long spin coherence times",
      "single substitutional nitrogen concentration",
      "charged nitrogen vacancy centres",
      "milled nanodiamonds",
      "negatively charged nitrogen vacancy"
    ],
    "tags": [
      "journal article"
    ],
    "publication": {
      "publisher": "APS",
      "journal": "Phys. Rev. B"
    },
    "note": {
      "typesetting": "TeX",
      "pages": 13,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}