Constraints on the uncertainties of entangled symmetric qubits
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.
- Publication:
-
Physics Letters A
- Pub Date:
- April 2007
- DOI:
- 10.1016/j.physleta.2006.11.073
- arXiv:
- arXiv:quant-ph/0601035
- Bibcode:
- 2007PhLA..364..203U
- Keywords:
-
- 03.67.-a;
- 03.65.-w;
- Quantum information;
- Quantum mechanics;
- Quantum Physics
- E-Print:
- 5 pages, REVTEX, Improved presentation