Thresholds for linear optics quantum computing with photon loss at the detectors

Journal Article · Thu Sep 15 04:00:00 EDT 2005 · Physical Review. A

DOI:https://doi.org/10.1103/PhysRevA.72.032307· OSTI ID:20718493

Silva, Marcus; Zalka, Christof ^[1]; Roetteler, Martin ^[2]

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1. Institute for Quantum Computing, University of Waterloo, 200 University Avenue W, Waterloo, Ontario, N2L 3G1 (Canada)
2. NEC Laboratories America, Inc., 4 Independence Way, Princeton, New Jersey 08540 (United States)

In order to place an upper bound on the tolerable amount of photon loss at the detectors, we calculate the error threshold for the linear optics quantum computing proposal by Knill, Laflamme, and Milburn [Nature (London) 409, 46 (2001)] under an error model where photon detectors have efficiency <100% but all other components - such as single photon sources, beam splitters, and phase shifters - are perfect and introduce no errors. We make use of the fact that the error model induced by the lossy hardware is that of an erasure channel, i.e., the error locations are always known. Using a method based on a Markov chain description of the error correction procedure, our calculations show that, with the 7 qubit Calderbank-Shor-Steane quantum code, the gate error threshold for fault tolerant quantum computation is bounded below by a value between 1.78% and 11.5% depending on the construction of the entangling gates.

• OSTI ID: 20718493
• Journal Information: Physical Review. A, Journal Name: Physical Review. A Journal Issue: 3 Vol. 72; ISSN 1050-2947; ISSN PLRAAN
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
CORRECTIONS
DATA TRANSMISSION
EFFICIENCY
ERRORS
MARKOV PROCESS
OPTICAL FIBERS
OPTICS
PHASE SHIFT
PHOTONS
QUANTUM COMPUTERS
QUANTUM ENTANGLEMENT
QUBITS