Issue
EPL
Volume 87, Number 2, July 2009
Article Number 20006
Number of page(s) 6
Section General
DOI http://dx.doi.org/10.1209/0295-5075/87/20006
Published online 18 August 2009
EPL, 87 (2009) 20006
DOI: 10.1209/0295-5075/87/20006

Stochastic local operations and classical communication properties of the n-qubit symmetric Dicke states

Dafa Li1, Xinxin Li2, Hongtao Huang3 and Xiangrong Li4

1   Department of Mathematical Sciences, Tsinghua University - Beijing 100084, China
2   Department of Computer Science, Wayne State University - Detroit, MI 48202, USA
3   Electrical Engineering and Computer Science Department, University of Michigan - Ann Arbor, MI 48109, USA
4   Department of Mathematics, University of California - Irvine, CA 92697-3875, USA

dli@math.tsinghua.edu.cn

received 14 May 2009; accepted in final form 17 July 2009; published July 2009
published online 18 August 2009

Abstract
Recently, several schemes for the experimental creation of Dicke states were described. In this paper, we show that all the n-qubit symmetric Dicke states with l (2 $\leqslant$ l $\leqslant$ (n-2)) excitations are inequivalent to the |GHZ$\rangle$ state or the |W$\rangle$ state under SLOCC, that the even n-qubit symmetric Dicke state with n/2 excitations is inequivalent to any even n-qubit symmetric Dicke state with l $\ne$ n/2 excitations under SLOCC, and that all the n-qubit symmetric Dicke states with l (2 $\leqslant$ l $\leqslant$ (n-2)) excitations satisfy Coffman, Kundu and Wootters' generalized monogamy inequality $C_{12}^{2}+\ldots +C_{1n}^{2} < C_{1(2\ldots n)}^{2} < 1$.

PACS
03.65.Ud - Entanglement and quantum nonlocality (e.g. EPR paradox, Bell's inequalities, GHZ states, etc.).
03.67.Mn - Entanglement measures, witnesses, and other characterizations.

© EPLA 2009