Abstract Based on a seven-qubit entangled state, Chen et al (2020 Int. J. Theor. Phys. 59 1402) presented a scheme for controlled quantum teleportation. Using the same quantum channel state, we put forward a new scheme in which the quantum information sender can also transmit a Bell state to receiver under the agreement and assist of the controller. The comparison with Chen et al’s scheme is made and reveals its distinct advantage of reducing the classical resource consumption and increasing the intrinsic efficiency as well as degrading the complexity of necessary operations.
Abstract Based on a seven-qubit entangled state, Chen et al (2020 Int. J. Theor. Phys. 59 1402) presented a scheme for controlled quantum teleportation. Using the same quantum channel state, we put forward a new scheme in which the quantum information sender can also transmit a Bell state to receiver under the agreement and assist of the controller. The comparison with Chen et al’s scheme is made and reveals its distinct advantage of reducing the classical resource consumption and increasing the intrinsic efficiency as well as degrading the complexity of necessary operations.
Abstract By utilizing the four-qubit cluster state as quantum channel, two efficient quantum schemes for teleporting an arbitrary single-qubit state in a controlled manner are put forward. In one scheme the controller needs to dominate a qubit only, while in another scheme the controller has to hold two qubits. The inspection of the necessary operations indicates that both schemes are feasible in terms of the current technologies. Moreover, these two schemes are compared with two competing schemes which employ the same quantum channel [i.e., the JM-schemes proposed by Jiang and Mo, Int. J. Theor. Phys. 56, 3084 (2017)]. It is found that, in contrast to the JM-schemes, the schemes we proposed have some prominent advantages, such as lower consumption of classical information, fewer necessary local quantum operations, and higher intrinsic efficiency.
In 2017, Min Li et al., presented a quantum teleportation scheme (Int. J. Theor. Phys. 56, 2710 (2017)) of five-qubit unknown quantum state using a seven - qubit entangled state as a quantum channel. Recently, Yong Yang et al., (Int. J. Theor. Phys. 57, 3485 – 3491 (2018)) have proposed an improved scheme of Min Li et al., [1] with only single-qubit measurements. In this teleportation scheme, we have shown that the quantum resource used by Min Li et al., for teleportation of five-qubit state is unnecessarily high and the teleportation task can be performed by using the minimum amount of quantum resource. So, in this scheme, we have proposed that the Min Li et al. and Yong Yang et al.’s scheme of quantum teleportation of five-qubit quantum state can be performed by using two pairs of any Bell states.
Abstract Several schemes for bidirectional controlled quantum teleportation (BCQT) of arbitrary single-qubit states have been proposed by utilizing five-qubit entangled states, six-qubit entangled state and seven-qubit entangled state as the quantum channels. In this paper, a generalization to BCQT of multi-qubit entangled states is presented. By using a five-qubit entangled state as the quantum channel, we propose a scheme for BCQT of certain class of multi-qubit entangled states in which two legitimate users exchange their unknown multi-qubit entangled state to each other with the help of a supervisor. Compared with previous BCQT (3 ↔ 3) scheme [2019 Int. J. Theor. Phys . 58 3594], our proposed BCQT (m ↔ n) scheme requires less consumption of quantum and classical resources, and possesses higher intrinsic efficiency. Also, the present BCQT scheme is more general and has less operation complexity.
In this paper, we propose a four-directional controlled quantum teleportation (CQT) by using a nine-qubit entangled state as the quantum channel. In 2020, a scheme for four-directional controlled quantum teleportation by using a 10-qubit state as the quantum resource had been proposed in X. W. Zha and K. Li [Mod. Phys. Lett. B 34, 2050412 (2020)] in which the controller has no control over the two teleportation processes. In this study, it is also shown that two receivers cannot reconstruct the original state sent from the respective senders and hence the teleportation processes cannot be completed in the previous scheme. However, these problems have been resolved in our proposed scheme in which the controller has control over all the teleportation processes and none of the receivers can reconstruct the original state sent from the respective senders without the permission of the controller. Thus, our proposed scheme reduces the consumption of quantum resource and is more secure and successful as compared to the previous scheme.
Abstract Based on a six-qubit entangled state, a quantum information processing scheme for teleporting a distinctive six-qubit state is presented. In the scheme, only Bell-state measurements and two-qubit controlled-NOT gate operations as well as some single-qubit transformed operations are needed. Compared with a rival scheme put forwarded by Tan et al [Int. J. Theor. Phys. 55, 155 (2016)], the present scheme is more simpler and easier to execute because it does not require to make the six-qubit entangled state measurement. Besides, it is deterministic and feasible in terms of the current experimental technologies.
Recently, Ri-Gui Zhou et al. [Int. J. Theor. Phys. 59, 166-172 (2020)] proposed a scheme for bidirectional quantum teleportation of two-two and two-three qubit states by utilizing a six-qubit entangled state as a quantum channel. It is observed that the intrinsic efficiency calculated by Zhou et al. is not correct. In this improved scheme, we show that bidirectional teleportation of two-two and two-three qubit quantum states can be done by using optimized quantum resource and less consumption of classical resource. We also calculate the intrinsic efficiency of our improved scheme which is much better than the Zhou's scheme. Additionally, we also discuss about the security of the protocol.