O. Jiménez, J. Bergou and A. Delgado
PHYSICAL REVIEW A 82 (2010)
We study the probabilistic cloning of three symmetric states. These states are defined by a single complex quantity, the inner product among them. We show that three different probabilistic cloning machines are necessary to optimally clone all possible families of three symmetric states. We also show that the optimal cloning probability of generating M copies out of 1 original can be cast as the quotient between the success probability of unambiguously discriminating 1 and M copies of symmetric states.