Efficient optical quantum information processing

W. J. Munro*, Kae Nemoto, T. P. Spiller, S. D. Barrett, Pieter Kok, R. G. Beausoleil

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review


Quantum information offers the promise of being able to perform certain communication and computation tasks that cannot be done with conventional information technology (IT). Optical quantum information processing (QIP) holds particular appeal, since it offers the prospect of communicating and computing with the same type of qubit. Linear optical techniques have been shown to be scalable, but the corresponding quantum computing circuits need many auxiliary resources. Here we present an alternative approach to optical QIP, based on the use of weak cross-Kerr nonlinearities and homodyne measurements. We show how this approach provides the fundamental building blocks for highly efficient non-absorbing single photon number resolving detectors, two qubit parity detectors, Bell state measurements and finally near deterministic control-not (CNOT) gates. These are essential QIP devices.

Original languageEnglish
Article numberS135
Number of pages6
JournalJournal of Optics B: Quantum and Semiclassical Optics
Issue number7
Early online date30 Jun 2005
Publication statusPublished - Jul 2005


  • Optical quantum computation
  • Efficient and scalable
  • Near deterministic gates

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