Optimal universal two-particle entanglement processes in arbitrary   dimensional Hilbert spaces
  Universal two-particle entanglement processes are analyzed in arbitrary dimensional Hilbert spaces. On the basis of this analysis the class of possible optimal universal entanglement processes is determined whose resulting output states do not contain any separable states. It is shown that these processes form a one-parameter family. For all Hilbert space dimensions larger than two the resulting optimally entangled output states are mixtures of anti-symmetric states which are freely entangled and which also preserve information about input states. Within this one-parameter family there is only one process by which all information about any input state is destroyed completely. 
G.Alber, A.Delgado, and I.Jex