%A Kan Wang, Xu-Tao Yu, Zai-Chen Zhang %T Two-qubit entangled state teleportation via optimal POVM and partially entangled GHZ state %0 Journal Article %D 2018 %J Front. Phys. %J Frontiers of Physics %@ 2095-0462 %R 10.1007/s11467-018-0832-9 %P 130320- %V 13 %N 5 %U {https://journal.hep.com.cn/fop/EN/10.1007/s11467-018-0832-9 %8 2018-10-19 %X

Quantum teleportation is of significant meaning in quantum information. In this paper, we study the probabilistic teleportation of a two-qubit entangled state via a partially entangled Greenberger- Horne-Zeilinger (GHZ) state when the quantum channel information is only available to the sender. We formulate it as an unambiguous state discrimination problem and derive exact optimal positive-operator valued measure (POVM) operators for maximizing the probability of unambiguous discrimination. Only one three-qubit POVM for the sender, one two-qubit unitary operation for the receiver, and two cbits for outcome notification are required in this scheme. The unitary operation is given in the form of a concise formula, and the fidelity is calculated. The scheme is further extended to more general case for transmitting a two-qubit entangled state prepared in arbitrary form. We show this scheme is flexible and applicable in the hop-by-hop teleportation situation.