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Abstract: Our concern is to remotely prepare a four-particle entangled cluster-type state with high success probabilities. By constructing some useful measurement bases, two novel schemes via different entanglement resources as the quantum channel are designed: one is via an EPR pair and two three-particle GHZ states; the other is via two four-qubit GHZ states. It is shown that through four-particle projective measurements under the novel sets of mutually orthogonal basis vectors, the original state can be successfully prepared with the probabilities and 1, respectively. These schemes are extended to the non-maximally entangled quantum channel. Compared with the previous remote preparation proposal, the success probabilities of the proposed schemes are greatly improved. Furthermore, the classical communication costs of these schemes are calculated to determine the classical resources required. [Copyright &y& Elsevier]

Abstract: Following some ideas of the quantum network coding protocol [Phys. Rev. A 76 (2007) 040301], we propose an efficient protocol to transmit two 2-level quantum states crossly over the butterfly network with two non-maximally entangled qubit pairs shared only between two senders. It is shown that both of the receivers can reestablish the initial states with a certain probability. And one classical bit communication can be saved at the bottleneck channel. Moreover, this protocol is generalized to the case of transmitting two multipartite entangled states. [Copyright &y& Elsevier]

Abstract: In this paper, by constructing some useful measurement bases, we first show that two senders can jointly prepare a three-qubit state of complex coefficients to a remote receiver via the shared three GHZ states. Then, the success probability can be improved by using the permutation group to classify the preparation state. Furthermore, under some different measurement bases, we propose another scheme to jointly prepare a three-qubit state of real coefficients with less restrictions. Finally, the present schemes are extended to multi-sender, and the classical communication costs of all the schemes are also calculated. [ABSTRACT FROM AUTHOR]