Document Type : Original Article


Physics Department, Faculty of Science, Razi University, Kermanshah, Iran


Quantum state discrimination between optical coherent superposition states is considered. The Helstrom bound for imperfect detection is evaluated. Under a physically realistic model of photodetection, we study several techniques for discriminating between optical coherent superposition states. We investigate quantum error probabilities for the Kennedy receiver, the Dolinar receiver and the unitary rotation scheme proposed by Sasaki and Hirota for sub-unity detector efficiency. Also, we study the feedback strategy employed by the Dolinar receiver to achieve the Helstrom bound for sub-unity detection efficiency.


Main Subjects

  1. C W Helstrom, “Quantum Detection and Estimation Theory”, Academic Press, New York (1976).
  2. R S Kennedy, Quaterly Progress Report. Tech. Rep. 110, Research Laboratory of Electronics, MIT, p. 219, unpublished (1972)
  3. M Sasaki and O Hirota, Rev. A 54 (1996) 2728.
  4. S Dolinar, Tech. Rep. 111, Research Laboratory of Electronics, MIT (1973)
  5. A Assalini, N D Pozza, and G Pierobon, Rev. A. 84 (2011) 022342.
  6. J M Geremia, Rev. A. 70 (2004) 062303.
  7. J P Gazeau, “Coherent states in quantum physics”, WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim (2009).
  8. A Ourjoumtsev, et al., Nature. 448 (2007) 784.
  9. B Vlastakis, et al., Science 342 (2013) 607.
  10. Loudon, “The Quantum Theory of Light”, Oxford University Press (1973).


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