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Title: Experimental determination of entanglement by a projective measurement

Abstract

We describe a method in which the entanglement of any pure quantum state can be experimentally determined by a simple projective measurement, provided the state is available in a twofold copy. We propose implementations of this approach for various systems and discuss in detail its first experimental realization, which employed twin photons entangled in two degrees of freedom, prepared in identical polarization and momentum states. We analyze the effect of errors due to imperfect state preparation.

Authors:
; ; ; ;  [1];  [2];  [3];  [4];  [4]
  1. Instituto de Fisica, Universidade Federal do Rio de Janeiro, Caixa Postal 68528, Rio de Janeiro, RJ 21941-972 (Brazil)
  2. (United States)
  3. (Brazil)
  4. (Germany)
Publication Date:
OSTI Identifier:
20982284
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 75; Journal Issue: 3; Other Information: DOI: 10.1103/PhysRevA.75.032338; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; DEGREES OF FREEDOM; PHOTONS; POLARIZATION; QUANTUM ENTANGLEMENT; QUANTUM MECHANICS

Citation Formats

Walborn, S. P., Ribeiro, P. H. Souto, Davidovich, L., Mintert, F., Buchleitner, A., Department of Physics, Harvard University, Cambridge, Massachusetts 02138, Instituto de Fisica, Universidade Federal do Rio de Janeiro, Caixa Postal 68528, Rio de Janeiro, RJ 21941-972, Max-Planck-Institut fuer Physik komplexer Systeme, Noethnitzer Strasse 38, D-01187 Dresden, and Max-Planck-Institut fuer Physik komplexer Systeme, Noethnitzer Strasse 38, D-01187 Dresden. Experimental determination of entanglement by a projective measurement. United States: N. p., 2007. Web. doi:10.1103/PHYSREVA.75.032338.
Walborn, S. P., Ribeiro, P. H. Souto, Davidovich, L., Mintert, F., Buchleitner, A., Department of Physics, Harvard University, Cambridge, Massachusetts 02138, Instituto de Fisica, Universidade Federal do Rio de Janeiro, Caixa Postal 68528, Rio de Janeiro, RJ 21941-972, Max-Planck-Institut fuer Physik komplexer Systeme, Noethnitzer Strasse 38, D-01187 Dresden, & Max-Planck-Institut fuer Physik komplexer Systeme, Noethnitzer Strasse 38, D-01187 Dresden. Experimental determination of entanglement by a projective measurement. United States. doi:10.1103/PHYSREVA.75.032338.
Walborn, S. P., Ribeiro, P. H. Souto, Davidovich, L., Mintert, F., Buchleitner, A., Department of Physics, Harvard University, Cambridge, Massachusetts 02138, Instituto de Fisica, Universidade Federal do Rio de Janeiro, Caixa Postal 68528, Rio de Janeiro, RJ 21941-972, Max-Planck-Institut fuer Physik komplexer Systeme, Noethnitzer Strasse 38, D-01187 Dresden, and Max-Planck-Institut fuer Physik komplexer Systeme, Noethnitzer Strasse 38, D-01187 Dresden. Thu . "Experimental determination of entanglement by a projective measurement". United States. doi:10.1103/PHYSREVA.75.032338.
@article{osti_20982284,
title = {Experimental determination of entanglement by a projective measurement},
author = {Walborn, S. P. and Ribeiro, P. H. Souto and Davidovich, L. and Mintert, F. and Buchleitner, A. and Department of Physics, Harvard University, Cambridge, Massachusetts 02138 and Instituto de Fisica, Universidade Federal do Rio de Janeiro, Caixa Postal 68528, Rio de Janeiro, RJ 21941-972 and Max-Planck-Institut fuer Physik komplexer Systeme, Noethnitzer Strasse 38, D-01187 Dresden and Max-Planck-Institut fuer Physik komplexer Systeme, Noethnitzer Strasse 38, D-01187 Dresden},
abstractNote = {We describe a method in which the entanglement of any pure quantum state can be experimentally determined by a simple projective measurement, provided the state is available in a twofold copy. We propose implementations of this approach for various systems and discuss in detail its first experimental realization, which employed twin photons entangled in two degrees of freedom, prepared in identical polarization and momentum states. We analyze the effect of errors due to imperfect state preparation.},
doi = {10.1103/PHYSREVA.75.032338},
journal = {Physical Review. A},
number = 3,
volume = 75,
place = {United States},
year = {Thu Mar 15 00:00:00 EDT 2007},
month = {Thu Mar 15 00:00:00 EDT 2007}
}
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