Recently, Li and Nie (Int. J. Theo. Phys. 52:1630, 2013) had introduced a bidirectional controlled quantum teleportation (BCQT) protocol by using GHZ-Bell state as a quantum channel. Also, Shukla et al. (Int. J. Theo. Phys. 52:3790, 2013) had shown the Li and Nie (LN) protocol is not a BCQT scheme. In this paper, two kinds of bidirectional teleportation schemes in order to correct and improve LN protocol are presented. In the first scheme, Alice and Bob as two legitimate users can simultaneously teleport an unknown single-qubit state to each other with the help of controller Charlie. In the second scheme, Alice can transmit two-qubit entangled state to Bob and at the same time Bob can teleport single-qubit state to Alice. In both of proposed schemes the quantum channel linking users is a GHZ-Bell state.
Recently, Li and Nie (Int. J. Theo. Phys. 52:1630, 2013) had introduced a bidirectional controlled quantum teleportation (BCQT) protocol by using GHZ-Bell state as a quantum channel. Also, Shukla et al. (Int. J. Theo. Phys. 52:3790, 2013) had shown the Li and Nie (LN) protocol is not a BCQT scheme. In this paper, two kinds of bidirectional teleportation schemes in order to correct and improve LN protocol are presented. In the first scheme, Alice and Bob as two legitimate users can simultaneously teleport an unknown single-qubit state to each other with the help of controller Charlie. In the second scheme, Alice can transmit two-qubit entangled state to Bob and at the same time Bob can teleport single-qubit state to Alice. In both of proposed schemes the quantum channel linking users is a GHZ-Bell state.
Abstract A bidirectional controlled quantum state teleportation (BCQST) scheme was proposed by Li et al (2013 Int. J. Theor. Phys. 52 1630) using a five-qubit composite Greenberger–Horne–Zeilinger-Bell state as the quantum channel. However, it was found to be unsuccessful for bidirectional teleportation control due to its own security loopholes (Shukla et al 2013 Int. J. Theor. Phys. 52 3790). In this paper, we put forward an improved version of the BCQST scheme so that the loopholes are fixed and the bidirectional control can indeed be achieved. In addition, after the improvement, the revised scheme becomes more feasible in terms of present experimental techniques.
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.
Since the first protocol of quantum teleportation based on an EPR pair was presented by Bennett et al. in 1993, it has become a hot topic in quantum communication. It is known that entanglement plays a key role in quantum teleportation. Various schemes of controlled quantum teleportation and bidirectional controlled quantum teleportation have been developed by using all kinds of multi-parties entangled states as a quantum channel, e.g. GHZ states, W states, 5-qubit cluster states, 6-qubit cluster states, 7-qubit cluster states, maximally entangled 5-qubit states, maximally entangled 6-qubit states, genuine entangled 6-qubit states, genuine entangled 7-qubit states, genuine entangled 8-qubit states. In this paper, a genuine entangled 9-qubit state is used as channel of quantum teleportation, and two schemes of bidirectional controlled quantum teleportation are proposed. One scheme is that with the control of Charlie Alice can transmit an arbitrary unknown qubit state to Bob and Bob can transmit an arbitrary unknown 3-qubit state to Alice in the same time. Another scheme is that with the control of Charlie Alice and Bob can transmit an arbitrary unknown 2-qubit to each other simultaneously. Compared with the existed schemes, our scheme can transmit more qubits of arbitrary state in total by an entangled state, and the intrinsic efficiency of our scheme is maybe the best. Moreover, the genuine entangled 9-qubit state used in our scheme can be produced through some simple quantum unitary gates.
In this paper, a theoretical scheme for bidirectional quantum teleportation by using a four-qubit GHZ state and two Bell states as a quantum channel is proposed. In this scheme, two arbitrary single-qubit quantum states and an unknown three-qubit state can be mutually transmitted between the two communication participants Alice and Bob. The quantum state information can be transmitted if Alice performs four single-qubit measurement operations on her qubits and Bob carries out a four-qubit joint measurement on his qubits, respectively. Then both Alice and Bob can reconstruct the target quantum state by means of appropriate unitary operations. Then we take comparisons with the other bidirectional quantum teleportation protocols in five aspects of quantum information bits transmitted, necessary operations, consumption of quantum resource, consumption of classical resource and intrinsic efficiency. Furthermore, we use channel authentication method to ensure the channel security and prove that our protocol can withstand four attack scenarios. It is concluded that our scheme has significant advantages of more qubits number transmitted, higher intrinsic efficiency and high security.
In this paper, a novel protocol is proposed for implementing BQCT by using five-qubit en The proposed protocol depends on the Controlled-NOT operation, proper single-qubit unitary operations and single-qubit measurement in the Z-basis and X-basis. The results showed that the protocol is more efficient from the perspective such as lower shared qubits and, single qubit measurements compared to the previous work. Furthermore, the probability of obtaining Charlie's qubit by eavesdropper is reduced, and supervisor can control one of the users or every two users. Also, we present a new method for transmitting n and m-qubits entangled states between Alice and Bob using proposed protocol.tangled states as a quantum channel which in the same time, the communicated users can teleport each one-qubit state to each other under permission of controller.
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.