Feedforward and its role in conditional linear optical quantum dynamics
Abstract
Nonlinear optical quantum gates can be created probabilistically using only singlephoton sources, linear optical elements, and photonnumberresolving detectors. These gates are heralded but operate with probabilities much less than 1. There is currently a large gap between the performance of the known circuits and the established upper bounds on their success probabilities. One possibility for increasing the probability of success of such gates is feedforward, where one attempts to correct certain failure events that occurred in the gate's operation. In this Brief Report we examine the role of feedforward in improving the success probability. In particular, for the nonlinear signshift gate, we find that in a threemode implementation with a single round of feedforward the optimal average probability of success is approximately given by p{sub success}=0.272. This value is only slightly larger than the general optimal success probability without feedforward, p{sub success}=0.25.
 Authors:
 QOLS, Blackett Laboratory, Imperial College London, Prince Consort Road, London SW7 2BW (United Kingdom)
 HewlettPackard Laboratories, Filton Road, Stoke Gifford, Bristol BS34 8QZ (United Kingdom)
 (United Kingdom)
 National Institute of Informatics, 212 Hitotsubashi, Chiyodaku, Tokyo 1018430 (Japan)
 Publication Date:
 OSTI Identifier:
 20787006
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. A; Journal Volume: 73; Journal Issue: 3; Other Information: DOI: 10.1103/PhysRevA.73.034301; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 74 ATOMIC AND MOLECULAR PHYSICS; GATING CIRCUITS; IMPLEMENTATION; NONLINEAR OPTICS; NONLINEAR PROBLEMS; PERFORMANCE; PHOTONS; PROBABILITY; QUANTUM MECHANICS
Citation Formats
Scheel, S., Munro, W. J., Kok, P., Eisert, J., Institute for Mathematical Sciences, Imperial College London, Prince's Gardens, London SW7 2PE, and Nemoto, K. Feedforward and its role in conditional linear optical quantum dynamics. United States: N. p., 2006.
Web. doi:10.1103/PHYSREVA.73.0.
Scheel, S., Munro, W. J., Kok, P., Eisert, J., Institute for Mathematical Sciences, Imperial College London, Prince's Gardens, London SW7 2PE, & Nemoto, K. Feedforward and its role in conditional linear optical quantum dynamics. United States. doi:10.1103/PHYSREVA.73.0.
Scheel, S., Munro, W. J., Kok, P., Eisert, J., Institute for Mathematical Sciences, Imperial College London, Prince's Gardens, London SW7 2PE, and Nemoto, K. Wed .
"Feedforward and its role in conditional linear optical quantum dynamics". United States.
doi:10.1103/PHYSREVA.73.0.
@article{osti_20787006,
title = {Feedforward and its role in conditional linear optical quantum dynamics},
author = {Scheel, S. and Munro, W. J. and Kok, P. and Eisert, J. and Institute for Mathematical Sciences, Imperial College London, Prince's Gardens, London SW7 2PE and Nemoto, K.},
abstractNote = {Nonlinear optical quantum gates can be created probabilistically using only singlephoton sources, linear optical elements, and photonnumberresolving detectors. These gates are heralded but operate with probabilities much less than 1. There is currently a large gap between the performance of the known circuits and the established upper bounds on their success probabilities. One possibility for increasing the probability of success of such gates is feedforward, where one attempts to correct certain failure events that occurred in the gate's operation. In this Brief Report we examine the role of feedforward in improving the success probability. In particular, for the nonlinear signshift gate, we find that in a threemode implementation with a single round of feedforward the optimal average probability of success is approximately given by p{sub success}=0.272. This value is only slightly larger than the general optimal success probability without feedforward, p{sub success}=0.25.},
doi = {10.1103/PHYSREVA.73.0},
journal = {Physical Review. A},
number = 3,
volume = 73,
place = {United States},
year = {Wed Mar 15 00:00:00 EST 2006},
month = {Wed Mar 15 00:00:00 EST 2006}
}

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