We propose a novel scheme for faithful bidirectional quantum teleportation (BQT) in which Alice can transmit an unknown N-qubit entangled state to Bob and at the same time Bob can transmit an unknown M-qubit entangled state to Alice by using a four-qubit entangled G-state as a quantum channel. We also propose a new scheme for cyclic QT of multi-qubit entangled states by using two G-states as a quantum channel. The advantage of our schemes is that it seems to be much simpler and requires reduced number of qubits in quantum channel as compared with the other proposed schemes.
We propose a novel scheme for faithful bidirectional quantum teleportation (BQT) in which Alice can transmit an unknown N-qubit entangled state to Bob and at the same time Bob can transmit an unknown M-qubit entangled state to Alice by using a four-qubit entangled G-state as a quantum channel. We also propose a new scheme for cyclic QT of multi-qubit entangled states by using two G-states as a quantum channel. The advantage of our schemes is that it seems to be much simpler and requires reduced number of qubits in quantum channel as compared with the other proposed schemes.
Abstract In this paper, we propose a new scheme for faithful bidirectional quantum teleportation (BQT) of special type of two-qubit entangled states by using single G state as a quantum channel. In 2016, by using five-qubit and six-qubit entangled states as the quantum channels, two different BQT schemes were proposed by Sang ((2016) Int. J. Theor. Phys . 55 , 1333) and Hassanpour et al ((2016) Quantum Inf. Process. 15 , 905) respectively. In first scheme, Alice teleports a special type of two-qubit entangled state to Bob and at the same time Bob teleports a single qubit state to Alice. In later scheme, Alice and Bob teleport special type of two-qubit entangled state to each other simultaneously. In contrast to these schemes, in our proposed scheme Alice and Bob can teleport special type of two-qubit entangled states to each other simultaneously while the quantum channel is a four-qubit entangled state. Our proposed BQT scheme requires minimum consumption of quantum and classical resources and it has maximum intrinsic efficiency as compared with previous BQT schemes. We also generalize our scheme for bidirectional quantum teleportation of N-qubit entangled states.
A novel scheme is proposed in this paper, which realizes the cyclic and bidirectional teleportation via pseudo multi-qubit entangled states. To realize the teleportation completely, it utilizes controlled-NOT operation to obtain a quantum channel whose number of qubits reaches twelve. In this scheme, Alice can teleport her qubits to Bob and Charlie, Bob can teleport his qubits to Alice and Charlie while Charlie teleports his qubits to Alice and Bob, respectively, they reconstruct the original state and make the scheme perfectly by performing Bell-state measurement and appropriate unitary operation.
In order to explore multi-directional quantum communication in a three-dimensional (3D) system, five-, seven- and [Formula: see text]-qutrit entangled states are constructed by 3D-Hadamard gates and 3D-controlled-NOT gates in this paper. Then a new scheme of controlled bidirectional quantum teleportation (QT) via five-qutrit entangled channel is proposed, where two observers can exchange their unknown single-qutrit states at the same time under the control of the supervisor. Along this mental, we propose a novel theoretical scheme to fulfil four-party controlled cyclic QT by using a seven-qutrit entangled state as the quantum channel, in which Alice can teleport an arbitrary unknown single-qutrit state to Bob, Bob can transmit an arbitrary single-qutrit state to Charlie, at the same time, Charlie can also teleport an arbitrary unknown single-qutrit state to Alice with the permission of the supervisor. In these schemes, only specific two-qutrit 3D-Bell state measurements, single-qutrit 3D-Z-basis measurements and suitable 3D-Weyl operators are needed, which can be implemented in physics easily. Moreover, the proposed four-party controlled cyclic scheme can be generalized into the case containing [Formula: see text] ([Formula: see text]) observers by using a [Formula: see text]-qutrit entangled channel. Analysis shows that the success probability of our schemes can reach 1. Through detailed discussion, we find that the security of our schemes and the control power of the supervisors can be guaranteed, and the intrinsic efficiency of the proposed schemes is relatively high.
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.
Abstract Cyclic quantum teleportation schemes requires at least the existence of three collaborators acting all as senders and receivers of quantum information, each one of them has an information to be transmitted to the next neighbour in a circular manner. Here, new cyclic quantum teleportation scheme is proposed for perfectly transmitting cyclically three arbitrary unknown two-qubit states ( α α , β β and γ γ ) among the three collaborators. In this scheme, Alice can send to Bob the quantum information contained in her two-qubit state α α and receive from Charlie the quantum information contained in the two-qubit state in his possession γ γ and similarly, Bob can transmit to Charlie the quantum information contained in his two-qubit state β β through a quantum channel of twelve-qubit state consisting of a six-qubit cluster state and a six-qubit entangled state by sequentially and cyclically performing Bell state measurements. Subsequently, each one of the three participants can afterwards retrieve his own desired two-qubit state using classical channel and by performing appropriate unitary Pauli operators and we have shown that our proposed scheme performs efficiently.