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Cited by 874Quantum Information and CryptographyQuantum Computing Algorithms and ArchitectureQuantum Mechanics and Applications

Experimental Quantum Computing without Entanglement

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Lanyon, B. P., Barbieri, M., Almeida, M. P., White, A. G.·2008·Physical Review Letters
DOI 10.1103/physrevlett.101.200501
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Abstract

Deterministic quantum computation with one pure qubit (DQC1) is an efficient model of computation that uses highly mixed states. Unlike pure-state models, its power is not derived from the generation of a large amount of entanglement. Instead it has been proposed that other nonclassical correlations are responsible for the computational speedup, and that these can be captured by the quantum discord. In this Letter we implement DQC1 in an all-optical architecture, and experimentally observe the generated correlations. We find no entanglement, but large amounts of quantum discord-except in three cases where an efficient classical simulation is always possible. Our results show that even fully separable, highly mixed, states can contain intrinsically quantum mechanical correlations and that these could offer a valuable resource for quantum information technologies.

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  • Recently there has been substantial progress in investigations of other possible candidates for AQS, such as photonic systems, photonic and polariton systems, and artificial lattices in solid state systems.

    “Recently there has also been substantial progress in investigations of other possible candidates for AQS, such as photonic systems [31, 32, 34-36], photonic and polariton systems [33, 38-42], artificial lattices in solid state systems [44].”

    From Can one trust quantum simulators? (2012) · cites this paper as [32]

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Research works printed but not linked: 14

  1. [5]E. Knill and R. Laflamme, Inf. Proc. Lett. 79 , 173 (2001).
  2. [6]P. W. Shor and S. P. Jordan, arXiv:0707.2831 (2007). · arXiv
  3. [7]R. D. Somma and S. Boixo, arXiv.org:0708.1330 (2007).
  4. [8]A. Datta and G. Vidal, Phys. Rev. A 75 , 042310 (pages 5) (2007).
  5. [9]R. Jozsa and N. Linden, Proc. R. Soc. London A 459 , 2011 (2003).
  6. [11]A. Datta, S. T. Flammia, and C. M. Caves, Phys. Rev. A 72 , 042316 (pages 14) (2005).
  7. [12]A. Datta, A. Shaji, and C. M. Caves, Phys. Rev. Lett. 100 , 050502 (pages 4) (2008).
  8. [13]B. Lanyon, M. Barbieri, M. P. Almeida, T. Jennewein, T. C. Ralph, K. J. Resch, A. Gilchrist, J. L. O'Brien, G. J. Pryde, and A. G. White, arXiv:0804.0272v1 (2008). · arXiv
  9. [14]C. A. Ryan, J. Emerson, D. Poulin, C. Negrevergne, and R. Laflamme, Physical Review Letters 95 , 250502 (pages 4) (2005).
  10. [16]P. Kok, W. J. Munro, K. Nemoto, T. C. Ralph, J. P. Dowling, and G. J. Milburn, Reviews of Modern Physics 79 , 135 (pages 40) (2007).
  11. [24]G. J. Pryde, J. L. O'Brien, A. G. White, and S. D. Bartlett, Physical Review Letters 94 , 220406 (pages 4) (2005).
  12. [25]N. K. Langford, T. J. Weinhold, R. Prevedel, K. J. Resch, A. Gilchrist, J. L. O'Brien, G. J. Pryde, and A. G. White, Phys. Rev. Lett. 95 , 210504 (pages 4) (2005).
  13. [26]N. Kiesel, C. Schmid, U. Weber, R. Ursin, and H. Weinfurter, Phys. Rev. Lett. 95 , 210505 (pages 4) (2005).
  14. [27]R. Okamoto, H. F. Hofmann, S. Takeuchi, and K. Sasaki, Phys. Rev. Lett. 95 , 210506 (pages 4) (2005).

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Authors
Lanyon, B. P., Barbieri, M., Almeida, M. P., & White, A. G.
Affiliations
The University of Queensland (AU)
ORCID
Venue
Physical Review Letters
Publisher
American Physical Society (APS)
Published
2008-11-13
Volume
101
Issue
20
Pages
200501-200501
ISSN
  • 0031-9007 (ISSN-L)
  • 1079-7114
DOI
10.1103/physrevlett.101.200501
OpenAlex
W1987315149
Cited by
874
References
29
Citations by year
2026: 5 · 2025: 26 · 2024: 25 · 2023: 26 · 2022: 31 · 2021: 41 · 2020: 31 · 2019: 29 · 2018: 32 · 2017: 50 · 2016: 48 · 2015: 72 · 2014: 72 · 2013: 103 · 2012: 124
FWCI
84.04
Type
journal article
Language
en
Open access
Licence
link.aps.org/licenses/aps-default-license (vor)
Locations
  • Physical Review Letters (publishedVersion)
  • PubMed (publishedVersion)
  • arXiv (Cornell University) (submittedVersion)
  • Iris (Roma Tre University) (submittedVersion)
  • arXiv (Cornell University)
Topics
  • Physical Sciences › Computer Science › Artificial Intelligence › Quantum Information and Cryptography
  • Physical Sciences › Computer Science › Artificial Intelligence › Quantum Computing Algorithms and Architecture
  • Physical Sciences › Physics and Astronomy › Atomic and Molecular Physics, and Optics › Quantum Mechanics and Applications
Keywords
quantum discord, nonclassical correlations, entanglement, classical simulation

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