Geometry of quantum states: new construction of positive maps

Dariusz Chruscinski, Andrzej Kossakowski

Published 2009-02-05Version 1

We provide a new class of positive maps in matrix algebras. The construction is based on the family of balls living in the space of density matrices of n-level quantum system. This class generalizes the celebrated Choi map and provide a wide family of entanglement witnesses which define a basic tool for analyzing quantum entanglement.