Review Article | Published:

Quantum computers

Nature volume 464, pages 4553 (04 March 2010) | Download Citation

Abstract

Over the past several decades, quantum information science has emerged to seek answers to the question: can we gain some advantage by storing, transmitting and processing information encoded in systems that exhibit unique quantum properties? Today it is understood that the answer is yes, and many research groups around the world are working towards the highly ambitious technological goal of building a quantum computer, which would dramatically improve computational power for particular tasks. A number of physical systems, spanning much of modern physics, are being developed for quantum computation. However, it remains unclear which technology, if any, will ultimately prove successful. Here we describe the latest developments for each of the leading approaches and explain the major challenges for the future.

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Acknowledgements

We thank R. Hanson, M. D. Lukin, and W. D. Oliver for comments. We acknowledge support from NSF, EPSRC, QIP IRC, IARPA, ERC, the Leverhulme Trust, CREST-JST, DFG, BMBF and Landesstiftung BW. J.L.O’B. acknowledges a Royal Society Wolfson Merit Award.

Author Contributions All authors contributed to all aspects of this work.

Author information

Author notes

    • T. D. Ladd

    Present address: HRL Laboratories, LLC, 3011 Malibu Canyon Road, Malibu, California 90265, USA.

Affiliations

  1. Edward L. Ginzton Laboratory, Stanford University, Stanford, California 94305-4088, USA

    • T. D. Ladd
  2. 3. Physikalisches Institut, Universität Stuttgart, Pfaffenwaldring 57, D-70550, Germany

    • F. Jelezko
  3. Institute for Quantum Computing,

    • R. Laflamme
  4. Department of Physics and Astronomy, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, N2L 3G1, Canada

    • R. Laflamme
  5. Perimeter Institute, 31 Caroline Street North, Waterloo, Ontario, N2L 2Y5, Canada

    • R. Laflamme
  6. Nano Electronics Research Laboratories, NEC Corporation, Tsukuba, Ibaraki 305-8501, Japan

    • Y. Nakamura
  7. The Institute of Physical and Chemical Research (RIKEN), Wako, Saitama 351-0198, Japan

    • Y. Nakamura
  8. Joint Quantum Institute, University of Maryland Department of Physics,

    • C. Monroe
  9. National Institute of Standards and Technology, College Park, Maryland 20742, USA

    • C. Monroe
  10. Centre for Quantum Photonics, H. H. Wills Physics Laboratory and Department of Electrical and Electronic Engineering, University of Bristol, Merchant Venturers Building, Woodland Road, Bristol, BS8 1UB, UK

    • J. L. O’Brien

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The authors declare no competing financial interests.

Corresponding author

Correspondence to J. L. O’Brien.

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https://doi.org/10.1038/nature08812

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