Entanglement swapping of two arbitrarily degraded entangled states

Brian T. Kirby, Siddhartha Santra, Vladimir S. Malinovsky, and Michael Brodsky
Phys. Rev. A 94, 012336 – Published 20 July 2016

Abstract

We consider entanglement swapping, a key component of quantum network operations and entanglement distribution. Pure entangled states, which are the desired input to the swapping protocol, are typically mixed by environmental interactions, causing a reduction in their degree of entanglement. Thus an understanding of entanglement swapping with partially mixed states is of importance. Here we present a general analytical solution for entanglement swapping of arbitrary two-qubit states. Our result provides a comprehensive method for analyzing entanglement swapping in quantum networks. First, we show that the concurrence of a partially mixed state is conserved when this state is swapped with a Bell state. Then, we find upper and lower bounds on the concurrence of the state resulting from entanglement swapping for various classes of input states. Finally, we determine a general relationship between the ranks of the initial states and the rank of the final state after swapping.

  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
  • Received 18 December 2015

DOI:https://doi.org/10.1103/PhysRevA.94.012336

©2016 American Physical Society

Physics Subject Headings (PhySH)

Quantum Information, Science & Technology

Authors & Affiliations

Brian T. Kirby*, Siddhartha Santra, Vladimir S. Malinovsky, and Michael Brodsky

  • United States Army Research Laboratory, Adelphi, Maryland 20783, USA

  • *brian.t.kirby4.ctr@mail.mil
  • Also at Department of Aeronautics and Astronautics, Stanford University, Stanford, California 94305, USA.

Article Text (Subscription Required)

Click to Expand

References (Subscription Required)

Click to Expand
Issue

Vol. 94, Iss. 1 — July 2016

Reuse & Permissions
Access Options
CHORUS

Article Available via CHORUS

Download Accepted Manuscript
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
×