Bound entanglement and continuous variables

Phys Rev Lett. 2000 Sep 25;85(13):2657-60. doi: 10.1103/PhysRevLett.85.2657.

Abstract

We introduce the definition of generic bound entanglement for the case of continuous variables. We provide some examples of bound entangled states for that case, and discuss their physical sense in the context of quantum optics. We raise the question of whether the entanglement of these states is generic. As a by-product we obtain a new many parameter family of bound entangled states with positive partial transpose. We also point out that the "entanglement witnesses" and positive maps revealing the corresponding bound entanglement can easily be constructed.