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Title: Entangled graphs. II. Classical correlations in multiqubit entangled systems

Journal Article · · Physical Review. A
 [1];  [1]
  1. Research Center for Quantum Information, Slovak Academy of Sciences, 845 11 Bratislava, (Slovakia)

Bipartite correlations in multiqubit systems cannot be shared freely. The presence of entanglement or classical correlation on certain pairs of qubits may imply correlations on other pairs. We present a method of characterization of bipartite correlations in multiqubit systems using a concept of entangled graphs which has been introduced in our earlier work [M. Plesch and V. Buzek, Phys. Rev. A 67, 012322 (2003)]. In entangled graphs, each qubit is represented by a vertex while the entanglement and classical correlations are represented by two types of edges. We prove by construction that any entangled graph with classical correlations can be represented by a mixed state of N qubits. However, not all entangled graphs with classical correlations can be represented by a pure state.

OSTI ID:
20639879
Journal Information:
Physical Review. A, Vol. 68, Issue 1; Other Information: DOI: 10.1103/PhysRevA.68.012313; (c) 2003 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 1050-2947
Country of Publication:
United States
Language:
English