Quantum-information division and an optimal uncorrelated channel

Abstract

We consider quantum-information division, which is characterized by a channel whose outputs have no correlation and are not completely randomized. We show that the quantum-information division is possible in a probabilistic manner by optimizing the average fidelity in the channel with $M$ outputs in both deterministic and probabilistic cases. Moreover, we show that the optimal fidelities drastically change depending on the condition imposed on the outputs (symmetric and asymmetric), which is quite in contrast to the case of imperfect cloning.