Entanglement enhancement is a key task for quantum technologies. This operation performed on states produced by parametric down-conversion sources has been the object of several recent experimental investigations. In particular, conditional preparation by photon-subtraction has been shown to improve the entanglement of these states. Here we analyse the role played by non-Gaussian and Gaussian measurements in more general entanglement concentration operations performed on a pair of two-mode squeezed vacua. We find stringent requirements for achieving an improved entanglement enhancement by measuring jointly these two resource states.
@article{arxiv.1302.3186,
title = {Requirements for two-source entanglement concentration},
author = {Mihai Vidrighin and Tim J. Bartley and Gaia Donati and Xian-Min Jin and Marco Barbieri and W. Steven Kolthammer and Animesh Datta and Ian A. Walmsley},
journal= {arXiv preprint arXiv:1302.3186},
year = {2013}
}
Comments
to appear on Quantum Measurements and Quantum Metrology