{
  "patent_number": "US 9256834",
  "country": "US",
  "title": "How Quantum Computers Use Special Devices to Control Qubits",
  "original_title": "Quantum computers having partial interferometric quantum gates",
  "summary": "This patent describes a way for quantum computers to control special quantum bits, called topological qubits, using a \"partial interferometric device\" to perform specific operations.",
  "what_it_does": "This patent describes a quantum computer design that uses a \"partial interferometric device\" to perform operations on \"topological qubits\" (Claim 1, 10, 16). This device can generate single qubit gates, like a \"θ/2 phase gate\" (Claim 2, 4), or \"entangling gates\" for multiple qubits (Claim 5). The core idea is to position specific \"target quasiparticles\" of the qubit within a central region of the interferometric device (Claim 3, 11). For example, a quantum computer could use a \"Fabry-Pérot double point contact interferometer\" (Claim 12) to apply a \"π/8 phase gate\" to a topological qubit made of \"Majorana zero mode quasiparticles\" (Claim 7, 8, 20).",
  "what_it_does_not_cover": [
    "Does not cover quantum operations that do not use a \"partial interferometric device\" as described.",
    "Does not cover quantum computers that only use non-topological qubits.",
    "Does not cover qubits formed from quasiparticles other than \"Ising-type\" or \"Majorana zero mode\" quasiparticles.",
    "Does not cover quantum gates that are not \"phase gates\" or \"qubit operators\" applied by the partial interferometric device.",
    "Does not cover interferometric devices that are not \"partial\" or do not include a \"Fabry-Pérot double point contact interferometer.\""
  ],
  "filed": "2013-12-16",
  "granted": "2016-02-09",
  "expires": "2033-12-16",
  "status": "active",
  "holder": "Microsoft Technology Licensing",
  "holder_url": "https://patentbrief.org/company/microsoft-technology-licensing",
  "inventors": [
    {
      "name": "Parsa Bonderson",
      "url": "https://patentbrief.org/inventor/parsa-bonderson"
    },
    {
      "name": "Michael H. Freedman",
      "url": "https://patentbrief.org/inventor/michael-h-freedman"
    }
  ],
  "times_cited": 12,
  "tags": [
    "quantum_computing",
    "semiconductors",
    "materials",
    "software"
  ],
  "abstract": "A quantum computer may include topologically protected quantum gates and non-protected quantum gates, which may be applied to topological qubits. The non-protected quantum gates may be implemented with a partial interferometric device. The partial interferometric device may include a Fabry-Pérot double point contact interferometer configured to apply “partial” interferometry to a topological qubit.",
  "url": "https://patentbrief.org/patent/us/9256834/quantum-computers-having-partial-interferometric-quantum-gates",
  "markdown_url": "https://patentbrief.org/patent/us/9256834/quantum-computers-having-partial-interferometric-quantum-gates/md",
  "google_patents_url": "https://patents.google.com/patent/US9256834",
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}