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Wang et al. first studied hierarchical quantum information splitting of an arbitrary single-qubit state via the χ state as the entangled channel. There exists a hierarchy among the three receivers as far as the power to recover the teleported state is concerned. But the scheme is considered in ideal environment. In this paper, we reinvestigate the scheme in amplitude-damping and phase-damping noises. The fidelity and average fidelity are adopted to quantify the effect of noise. It is found that they are both dependent on the coefficients of the teleported state and the noise parameter. Moreover, we put forward a novel deterministic scheme to realize hierarchical controlled remote preparation of an arbitrary single-qubit state. Comparing with the previous scheme via the χ state, the sender does not need to perform information dividing due to the subtly constructed measurement basis. We also consider the proposed scheme under noisy environment. [ABSTRACT FROM AUTHOR]

Two schemes via different entangled resources as the quantum channel are proposed to realize remote preparation of an arbitrary four-particle $$\chi $$ -state with high success probabilities. To design these protocols, some useful and general measurement bases are constructed, which have no restrictions on the coefficients of the prepared states. It is shown that through a four-particle projective measurement and two-step three-particle projective measurement under the novel sets of mutually orthogonal basis vectors, the original state can be prepared with the probability 50 and 100 %, respectively. And for the first scheme, the special cases of the prepared state that the success probability reaches up to 100 % are discussed by the permutation group. Furthermore, the present schemes are extended to the non-maximally entangled quantum channel, and the classical communication costs are calculated. [ABSTRACT FROM AUTHOR]

In this paper, we show that some special mixed quantum resource experience the same property of pure entanglement such as Bell state for quantum teleportation. It is shown that one mixed state and three bits of classical communication cost can be used to teleport one unknown qubit compared with two bits via pure resources. The schemes are easily implement with model physical techniques. Moreover, these resources are also optimal and typical for faithfully remotely prepare an arbitrary qubit, two-qubit and three-qubit states with mixed quantum resources. Our schemes are completed as same as those with pure quantum entanglement resources except only 1 bit additional classical communication cost required. The success probability is independent of the form of the mixed resources. [ABSTRACT FROM AUTHOR]

By constructing some useful measurement bases, we put forward two novel schemes via different entanglement resources to realize remote preparation of a six-particle entangled cluster-type state with high probabilities. It is shown that through a three-particle projective measurement and two-step two-particle projective measurement under the novel sets of mutually orthogonal basis vectors, the original state can be prepared with the probability 50 % and 100 %, respectively. And for the first scheme, the special cases of the prepared state that the success probability reaches up to 100 % are discussed by the permutation group. Compared with the previous proposal, the success probabilities of the proposed schemes are greatly improved. Furthermore, the present schemes are extended to the non-maximally entangled quantum channel, and the classical communication costs are calculated. [ABSTRACT FROM AUTHOR]

In this paper, several new protocols for the controlled remote state preparation (CRSP) by using the Brown state as the quantum channel are proposed. Firstly, we propose a CRSP protocol of an arbitrary two qubit state. Then, the CRSP protocol of an arbitrary three qubit state, which has rarely been considered by the previous papers, is investigated. The coefficients of the prepared states can be not only real, but also complex. To design these protocols, some useful and general measurement bases are constructed, which can greatly reduce the restrictions for the coefficients of the prepared states. The security analysis is provided in detail. Moreover, receiver's all recovery operations are summarized into a concise formula. [ABSTRACT FROM AUTHOR]

We propose a deterministic and faithful scheme for realizing the assisted clone of an unknown two-particle entangled state. The first stage of the protocol requires teleportation via maximal entanglement. In the second stage, a novel set of mutually orthogonal basis vectors is constructed. With the assistance of the preparer through a two-particle projective measurement under this basis, a perfect copy of an original state can be produced. Compared with the previous protocols which produce the unknown state and its orthogonal complement state at the site of the sender, our scheme generates the unknown state deterministically. On the other hand, we put forward another assisted clone scheme via nonmaximal entanglement as the quantum channel. A faithful copy of the unknown state can be obtained with a certain probability. [ABSTRACT FROM AUTHOR]

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]