Entanglement versus entropy for a class of mixed two-qutrit states

Abstract

We compute the measure of entanglement for some classes of states belonging to the simplex of Bell-diagonal states of two qutrits introduced by Baumgartner et al. [Phys. Rev. A 74, 032327 (2006)]. We discuss also partial characterization of that simplex in terms of negativity and linear entropy. A numerical exploration of the entropy-entanglement plane indicates that, in the analogy to the two-qubit case [Munro et al., Phys. Rev. A 64, 030302(R) (2001)], two-qutrit Werner states do not maximize entanglement for a given entropy.