Local Invariants and Pairwise Entanglement in Symmetric Multi-qubit System
Quantum Physics
2007-05-23 v2
Abstract
Pairwise entanglement properties of a symmetric multi-qubit system are analyzed through a complete set of two-qubit local invariants. Collective features of entanglement, such as spin squeezing, are expressed in terms of invariants and a classifcation scheme for pairwise entanglement is proposed. The invariant criteria given here are shown to be related to the recently proposed (Phys. Rev. Lett. 95, 120502 (2005)) generalized spin squeezing inequalities for pairwise entanglement in symmetric multi-qubit states.
Cite
@article{arxiv.quant-ph/0509056,
title = {Local Invariants and Pairwise Entanglement in Symmetric Multi-qubit System},
author = {A. R. Usha Devi and M. S. Uma and R. Prabhu and Sudha},
journal= {arXiv preprint arXiv:quant-ph/0509056},
year = {2007}
}
Comments
9 pages, 2 figures, REVTEX, Replaced with a published version