We propose two protocols for remotely preparing a two-qubit entangled state, where the quantum channels take the form of one-dimensional four-qubit cluster and cluster-class states, respectively. The total success probability and classical communication cost are also calculated.
A scheme is proposed for remotely preparing a two-qubit state by using four-qubit cluster state as the quantum channel.In the scheme,the success probability of preparation and classical communication cost are calculated.In general,Bob can successfully prepare the target state with the probability 1/4 and consume only 1/4 bits classical communication.However,if the state belongs to six special situations,the success probability of preparation can reach 1/2 or even 1 after consuming some extra bits.
Using partial entangled states as the quantum channel, two schemes for probabilistic remote preparation of the four-particle cluster-type state with real and complex coefficients are presented. In the first scheme, the sender and the receiver share two partial Bell states and one partial three-qubit GHZ stats as the quantum channel, and the sender can help a remote receiver to prepare a four-particle entangled cluster-type state by using three-qubit projective measurements with certain probability. In the second scheme, the quantum channel is composed of two partial three-qubit GHZ states, the remote state preparation (RSP) can be successfully realized via the positive operator valued measure (POVM), and the two-particle projective measurements are also needed in this process. The total success probability and classical communication cost are calculated.
We present a protocol for probabilistic remote preparation of a four-particle entangled W state. The quantum channel is composed of two partial entangled four-particle cluster states. We calculate the total successful probability and total classical communication cost required for the general case and for all kinds of the special cases, respectively. It is shown that for two maximally entangled four-particle cluster states, such a scheme for the general case has the total successful probability of 25% and only consumes the total classical communication of 1 bit, while this scheme for the special cases under certain conditions can possess successful probability of 50% or 100%, the required classical communication will only be 2 bits or 4 bits. Meantime, we give in detail all unitary transformations for the general case and for all kinds of the special cases, respectively.
By joint actions of two separate two-qubit projective measurements, I present a new protocol for remotely preparing a two-qubit state via the shared three bipartite entanglements. The success probability and the classical communication cost are also minutely calculated. Then I concisely generalize it to multi-party case and multi-qubit state case, respectively. In contrast to the previous schemes [Int. J. Theor. Phys.48 (2009) 2005; Int. J. Theor. Phys.46 (2007) 2378; Commun. Theor. Phys.47 (2007) 247], this protocol has distinct advantages overwhelming the above ones as far as quantum resource consumption and quantum operation difficulty or intensity are concerned.
An explicit scheme for probabilistically teleporting an arbitrary two-qubit state is proposed by using a one-dimensional four-qubit cluster-class state as the quantum channel. In the scheme, the sender first performs two Bell state measurements (BSMs). Then with the sender's help, the receiver can reconstruct the original state probabilistically by introducing an auxiliary qubit and making appropriate unitary operations. Moreover, the total success probability and classical communication cost of the present scheme are also calculated.