Experimental demonstration of optimal unambiguous state discrimination

Roger B.M. Clarke, Anthony Chefles, Stephen M. Barnett, Erling Riis

Research output: Contribution to journalArticle

8 Citations (Scopus)
51 Downloads (Pure)


We present a full demonstration of unambiguous state discrimination between nonorthogonal quantum states. Using a free-space interferometer we have realized the optimum quantum measurement scheme for two nonorthogonal states of light, known as the Ivanovic-Dieks-Peres (IDP) measurement. We have gained access to all three possible outcomes of this measurement. All aspects of this generalized measurement scheme, including its superiority over a standard von Neumann measurement, have been demonstrated within 1.5% of the IDP predictions.
Original languageEnglish
Pages (from-to)040305-1-040305-4
JournalPhysical Review A
Issue number4
Publication statusPublished - 21 Mar 2001


  • optics
  • quantum physics
  • optimal unambiguous state discrimination
  • Ivanovic-Dieks-Peres measurement

Cite this