Non-decomposable quantum dynamical semigroups and bound entangled states
arXiv:quant-ph/0411095
Abstract
We use open quantum system techniques to construct one-parameter semigroups of positive maps and apply them to study the entanglement properties of a class of 16-dimensional density matrices, representing states of a 4x4 bipartite system.
15 pages, to appear on "Open systems & information dynamics", OSID style