文摘
We investigate the probabilistic quantum cloning (PQC) of two states with arbitrary probability distribution. The optimal success probabilities are worked out for \(1\rightarrow 2\) PQC of the two states. The results show that the upper bound on the success probabilities of PQC in Qiu (J Phys A 35:6931–6937, 2002) cannot be reached in general. With the optimal success probabilities, we design simple forms of \(1\rightarrow 2\) PQC and work out the unitary transformation needed in the PQC processes. The optimal success probabilities for \(1\rightarrow 2\) PQC are also generalized to the \(M\rightarrow N\) PQC case. Keywords Probabilistic quantum cloning Optimal success probabilities Unitary transformation