Constraints on the uncertainties of entangled symmetric qubits

2006/01/31 by A. R. Usha Devi, M. S. Uma, R. Prabhu +1 · 2 citations
Computer Science · Physics and Astronomy · #Quantum Computing Algorithms and Architecture #Quantum Information and Cryptography #Quantum Mechanics and Applications #quant-ph

paper · pdf · doi:10.1016/j.physleta.2006.11.073

published as Phys. Lett. A 364, 203 (2007) · 5 pages, REVTEX, Improved presentation; Theorem on neccessary and sufficient condition included; To appear in Phys. Lett. A

arxiv created 2006/11/29 · openalex publication_date 2006/12/06 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28

Abstract

We derive necessary and sufficient inseparability conditions imposed on the variance matrix of symmetric qubits. These constraints are identified by examining a structural parallelism between continuous variable states and two qubit states. Pairwise entangled symmetric multiqubit states are shown here to obey these constraints. We also bring out an elegant local invariant structure exhibited by our constraints.

Citations

• Separability Criterion for Density Matrices
• Non-local properties of a symmetric two-qubit system
• Scalable multi-particle entanglement of trapped ions
• Experimental demonstration of quantum memory for light

Cited by

• Characterization of entanglement in multiqubit systems via spin squeezing
• Practical schemes for the measurement of angular-momentum covariance matrices in quantum optics