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We present a scheme for implementing deterministic joint remote preparation of the Knill–Laflamme–Milburn state with two GHZ states as the quantum channel. Assuming that four of the six involved qubits collectively suffer the same type of noise, we first investigate the effects of four typical types of noises on the protocol by means of Kraus operators. It is shown that the bit-flip and amplitude damping noise are the severe noises for decoherence rate χ < 0.5 , followed by the depolarizing and phase-flip channel, respectively. Interestingly, the efficiency of the scheme can be restored by adding decoherence when χ > 0.5 in bit-flip and phase-flip noise channel. Afterward, we investigate the dynamics of deterministic joint remote state preparation for dissipative environments. Analytical and numerical calculations show that the quality of our scheme can be enhanced by adjusting the system detuning no matter whether the non-Markovian effect is applicable or not. [ABSTRACT FROM AUTHOR]

We present two schemes for deterministic assisted clone(DAC) of an unknown two- and three-qubit entangled states with assistance via muti-qubit Brown state. In the schemes, the sender wish to teleport an unknown original entangled state which from the state preparer, and then create a perfect copy of the unknown state at her place. The DAC schemes include two stages. The first stage requires teleportation with Bell-state measurements via a five-qubit Brown state(or seven-qubit Brown state) as the quantum channel. In the second stage, to help the sender realize the quantum cloning, the state preparer performs projective measurements on their own particles which from the sender, then the sender can acquire a perfect copy of the unknown state by means of some appropriate unitary operations. Furthermore, the total success probability for assisted cloning a perfect copy of the unknown state can reach 1 in our schemes. [ABSTRACT FROM AUTHOR]

Several schemes for deterministic remote preparation of four-qubit W state by using four Einstein-Podolsky-Rosen (EPR) pairs and two four-qubit GHZ entangled states as quantum channels were proposed. To complete the schemes, four-qubit projective measurement and two-qubit projective measurement are needed respectively. Compared with the previous schemes which the total probability of successful RSP is $\frac {1}{4}$, it is shown that the total successful probability in our schemes can reach 1. [ABSTRACT FROM AUTHOR]

For N+1-sender independently share the classical knowledge of a quantum state, a new scheme for joint remote preparation of four-particle cluster-type states using only two partially two-particle entangled states as quantum channel is presented. In our scheme, each of the senders is just required to perform a bipartite projective measurement, and the receiver adopts some appropriate unitary operation to obtain the original state with certain probability. We also discuss four type information-splitting methods which can make the receiver obtain the unknown state. The classical communication cost is also calculated. [ABSTRACT FROM AUTHOR]

We present a scheme for implementing tripartite controlled teleportation of an arbitrary two-qubit entanglement state with the genuine pentaqubit entangled state and generate the quantum channel and then demonstrated the feasibility of probabilistic controlled teleportation in cavity QED. We also used fidelity and concurrence to quantify the efficiency of the protocol in noisy environment. Several noise scenarios are investigated in which the bit of the controller and the receiver are subjected to the same or different types of noise. The result has shown that in some specially noise scenario, lower fidelity means higher entanglement for output state and it also exhibits more noise which leads to more efficiency for entanglement. [ABSTRACT FROM AUTHOR]