Letters in Mathematical Physics

, Volume 70, Issue 1, pp 57–64 | Cite as

Computable Cross-norm Criterion for Separability

  • Oliver Rudolph


We describe a computable analytical criterion for separability of bipartite mixed states in arbitrary dimension. The criterion stipulates that a certain norm on the state space (the computable cross-norm) is bounded by 1 for separable states. The criterion is shown to be independent of the well-known positive partial transpose (PPT) criterion. In other words, the criterion detects some bound entangled states but fails for some free entangled states.

entanglement separability criteria projective tensor norm cross-norms 


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Copyright information

© Kluwer Academic Publishers 2004

Authors and Affiliations

  • Oliver Rudolph
    • 1
  1. 1.Quantum Information Theory Group, Istituto Nazionale per la Fisica della Materia and Dipartimento di Fisica A. Volta'Università di Pavia, via Bassi 6PaviaItaly

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