Separability bounds on multiqubit moments due to positivity under partial transpose

Simple item page
dc.creatorDevi, A R Usha
dc.creatorRajagopal, A K
dc.date2008-08-19
dc.date2008-12-01
dc.date.accessioned2026-07-07T12:20:39Z
dc.date.available2026-07-07T12:20:39Z
dc.descriptionPositivity of the density operator reflects itself in terms of sequences of inequalities on observable moments. Uncertainty relations for non-commuting observables form a subset of these inequalities. In addition, criterion of positivity under partial transposition (PPT) imposes distinct bounds on moments, violations of which signal entanglement. We present bounds on some novel sets of composite moments, consequent to positive partial transposition of the density operator and report their violation by entangled multiqubit states. In particular, we derive separability bounds on a multiqubit moment matrix (based on PPT constraints on bipartite divisions of the density matrix) and show that three qubit pure states with non-zero tangle violate these PPT moment constraints. Further, we recover necessary and sufficient condition of separability in a multiqubit Werner state through PPT bounds on moments.
dc.description16 pages, no figures, minor revisions, references added; To appear in Phys. Rev. A
dc.identifierhttps://arxiv.org/abs/0808.2581
dc.identifierhttp://arxiv.org/abs/0808.2581
dc.identifierPhys. Rev. A 78, 062334 (2008).
dc.identifierdoi:10.1103/PhysRevA.78.062334
dc.identifier.urihttp://salesiana.dossiersoluciones.com/handle/123456789/213127
dc.subjectQuantum Physics
dc.titleSeparability bounds on multiqubit moments due to positivity under partial transpose
dc.typetext

Files

Collections

arXiv