关键词: 量子概率隐形传态, cluster 态, Bell态测量, 幺正变换, 量子控制相位门, probabilisticquantum teleportation, cluster state, Bell state measurement, unitary transformation, quantum controlled phase gate

Abstract: Two schemes for teleporting an unknown two-particle entangled state via a four-qubit non-maximally entangled cluster state as quantum channel are proposed. In the first scheme, we teleported a special bipartite entangled state, the receiver Bob can reconstruct the original state with a certain probability according to the sender Alice’s measurement results, and the successful probability is determined by the smallest two coefficients’ absolute values of the cluster state. In the latter scheme we teleported an arbitrary two-particle entangled state. Contrast to the first scheme, Bob should perform a quantum controlled phase gate operation besides the unitary transformation. The considerable advantage of our schemes is that we employ a non-maximally entangled cluster state as quantum channel in these two schemes, which differs from the paper [Li D C, Cao Z L. Commun. Theor. Phys., 2007, 47:464]. Thus, our schemes can greatly reduce the amount of entanglement resources and need less classical bits.