Experimental Demonstration of Adaptive Quantum State Estimation

Ryo Okamoto, Minako Iefuji, Satoshi Oyama, Koichi Yamagata, Hiroshi Imai, Akio Fujiwara, and Shigeki Takeuchi
Phys. Rev. Lett. 109, 130404 – Published 28 September 2012


The first experimental demonstration of an adaptive quantum state estimation (AQSE) is reported. The strong consistency and asymptotic efficiency of AQSE have been mathematically proven [A. Fujiwara, J. Phys. A 39, 12489 (2006)]. In this Letter, the angle of linear polarization of single photons, the phase parameter between the right and the left circularly polarization, is estimated using AQSE, and the strong consistency and asymptotic efficiency are experimentally verified. AQSE will provide a general useful method in both quantum information processing and metrology.

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  • Received 30 January 2012


© 2012 American Physical Society

Authors & Affiliations

Ryo Okamoto1,2, Minako Iefuji1,2, Satoshi Oyama1,2, Koichi Yamagata3, Hiroshi Imai4, Akio Fujiwara3,*, and Shigeki Takeuchi1,2,†

  • 1Research Institute for Electronic Science, Hokkaido University, Kita-ku, Sapporo 001-0020, Japan
  • 2The Institute of Scientific and Industrial Research, Osaka University, Mihogaoka 8-1, Ibaraki, Osaka 567-0047, Japan
  • 3Department of Mathematics, Osaka University, 1-1 Machikaneyama, Toyonaka, 560-0043 Osaka, Japan
  • 4University of Pavia, Dipartimento di Fisica A. Volta, Via Bassi 6, 27100 Pavia, Italy

  • *fujiwara@math.sci.osaka-u.ac.jp
  • takeuchi@es.hokudai.ac.jp

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Vol. 109, Iss. 13 — 28 September 2012

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