Superadditivity of distillable entanglement from quantum teleportation
Abstract
We show that the phenomenon of superadditivity of distillable entanglement observed in multipartite quantum systems results from the consideration of states created during the execution of the standard endtoend quantum teleportation protocol [and a few additional local operations and classical communication (LOCC) steps] on a linear chain of singlets. Some of these intermediate states are tensor products of bound entangled (BE) states, and hence, by construction possess distillable entanglement, which can be unlocked by simply completing the rest of the LOCC operations required by the underlying teleportation protocol. We use this systematic approach to construct both new and known examples of superactivation of bound entanglement, and examples of activation of BE states using other BE states. A surprising outcome is the construction of noiseless quantum relay channels with no distillable entanglement between any two parties, except for that between the two end nodes.
 Authors:
 Centre for Quantum Information and Quantum Control and Department of Chemistry, University of Toronto, Toronto, Ontario, M5S 3H6 (Canada)
 (United States)
 Publication Date:
 OSTI Identifier:
 20786238
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. A; Journal Volume: 72; Journal Issue: 6; Other Information: DOI: 10.1103/PhysRevA.72.060303; (c) 2005 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 74 ATOMIC AND MOLECULAR PHYSICS; DATA TRANSMISSION; ENERGY LEVELS; INTERMEDIATE STATE; QUANTUM ENTANGLEMENT; QUANTUM MECHANICS; QUANTUM TELEPORTATION; TENSORS
Citation Formats
Bandyopadhyay, Somshubhro, Roychowdhury, Vwani, and Electrical Engineering Department, UCLA, Los Angeles, California 90095. Superadditivity of distillable entanglement from quantum teleportation. United States: N. p., 2005.
Web. doi:10.1103/PHYSREVA.72.0.
Bandyopadhyay, Somshubhro, Roychowdhury, Vwani, & Electrical Engineering Department, UCLA, Los Angeles, California 90095. Superadditivity of distillable entanglement from quantum teleportation. United States. doi:10.1103/PHYSREVA.72.0.
Bandyopadhyay, Somshubhro, Roychowdhury, Vwani, and Electrical Engineering Department, UCLA, Los Angeles, California 90095. Thu .
"Superadditivity of distillable entanglement from quantum teleportation". United States.
doi:10.1103/PHYSREVA.72.0.
@article{osti_20786238,
title = {Superadditivity of distillable entanglement from quantum teleportation},
author = {Bandyopadhyay, Somshubhro and Roychowdhury, Vwani and Electrical Engineering Department, UCLA, Los Angeles, California 90095},
abstractNote = {We show that the phenomenon of superadditivity of distillable entanglement observed in multipartite quantum systems results from the consideration of states created during the execution of the standard endtoend quantum teleportation protocol [and a few additional local operations and classical communication (LOCC) steps] on a linear chain of singlets. Some of these intermediate states are tensor products of bound entangled (BE) states, and hence, by construction possess distillable entanglement, which can be unlocked by simply completing the rest of the LOCC operations required by the underlying teleportation protocol. We use this systematic approach to construct both new and known examples of superactivation of bound entanglement, and examples of activation of BE states using other BE states. A surprising outcome is the construction of noiseless quantum relay channels with no distillable entanglement between any two parties, except for that between the two end nodes.},
doi = {10.1103/PHYSREVA.72.0},
journal = {Physical Review. A},
number = 6,
volume = 72,
place = {United States},
year = {Thu Dec 15 00:00:00 EST 2005},
month = {Thu Dec 15 00:00:00 EST 2005}
}

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