Representation of entanglement by negative quasiprobabilities

J. Sperling and W. Vogel
Phys. Rev. A 79, 042337 – Published 28 April 2009; Erratum Phys. Rev. A 80, 029905 (2009)

Abstract

Any bipartite quantum state has quasiprobability representations in terms of separable states. For entangled states these quasiprobabilities necessarily exhibit negativities. Based on the general structure of composite quantum states, one may reconstruct such quasiprobabilities from experimental data. Because of ambiguity, the quasiprobabilities obtained by the bare reconstruction are insufficient to identify entanglement. An optimization procedure is introduced to derive quasiprobabilities with a minimal amount of negativity. Negativities of optimized quasiprobabilities are necessary and sufficient for entanglement; their positivity proves separability.

  • Figure
  • Figure
  • Received 27 November 2008

DOI:https://doi.org/10.1103/PhysRevA.79.042337

©2009 American Physical Society

Erratum

Authors & Affiliations

J. Sperling* and W. Vogel

  • Arbeitsgruppe Quantenoptik, Institut für Physik, Universität Rostock, D-18051 Rostock, Germany

  • *jan.sperling2@uni-rostock.de
  • werner.vogel@uni-rostock.de

Article Text (Subscription Required)

Click to Expand

References (Subscription Required)

Click to Expand
Issue

Vol. 79, Iss. 4 — April 2009

Reuse & Permissions
Access Options
Author publication services for translation and copyediting assistance advertisement

Authorization Required


×
×

Images

×

Sign up to receive regular email alerts from Physical Review A

Log In

Cancel
×

Search


Article Lookup

Paste a citation or DOI

Enter a citation
×