Bidirectional Quantum Teleportation Scheme Research Articles

Scheme for Bidirectional Quantum Teleportation of Unknown Electron-Spin States of Quantum Dots within Single-Sided Cavities

We represent the mutual swapping of two unknown states using bidirectional quantum teleportation (BQT) while transferring a single photon. In our BQT scheme, two users (Alice and Bob) can mutually teleport their two unknown states of the electron-spin in quantum dots (QDs) embedded in single-sided cavities. For this BQT scheme, we employ the interactions of a photonic spin (photon) and an electron-spin (excess electron) of QDs confined in a single-sided cavity, which is feasible in practice. The previous BQT scheme which used cross-Kerr nonlinearities (XKNLs) and X-homodyne detection was inevitable the decoherence effect in optical fibers. Consequently, the proposed BQT scheme can enhance an experimental implementation with the use of QD-cavity systems under the decoherence effect and this can also be realized with current technology, compared with the previous BQT scheme based on XKNLs.

Improving the Bidirectional Quantum Teleportation Scheme via Five-qubit Cluster State

A bidirectional quantum teleportation scheme is presented recently by Ming-huang Sang (Int. J. Theor. Phys. 55, 1333, 2016) via a five-qubit cluster state as quantum channel. In the scheme a special two-qubit entangled state and an arbitrary single-qubit state can be transmitted to each other’s users. In this paper, with the same quantum resources, we put forward an improved scheme, in which the two-qubit non-local operations are not required. In comparison to the original, our improved scheme has some apparent merits, such as lower complexity (intensity and difficulty) of necessary operations, less consumption of classical resources, higher intrinsic efficiency and stronger flexibility of scheme, and so on.

Bidirectional quantum teleportation of two-qubit entangled state by using G-state as a quantum channel

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.

Bidirectional Quantum Teleportation by Using a Four-Qubit GHZ State and Two Bell States

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.

Quantum Handshake Beacon in Communication System Using Bidirectional Quantum Teleportation

Network security is essential for communication system. In this paper, we propose a quantum handshake beacon (QHB) protocol based on bidirectional quantum teleportation (BQT) to improve the network security. The BQT scheme for the proposed protocol is designed, including three operators: Alice, Bob and Charlie. Alice and Bob transmit an unknown qubit to each other simultaneously, while Charlie controls the trigger qubits and a Greenberger-Horne-Zeilinger (GHZ) state is shared among them. The qubits to be transmitted as handshake beacon go through different quantum gates and the corresponding unitary transformations are performed on the qubits according to the measurement outcomes. With different trigger qubits, the BQT scheme can achieve unidirectional teleportation with fidelity 1 or bidirectional teleportation with different fidelities. We analyze the fidelity of both sides in BQT with the joint probability of the trigger qubits and point out the area of fidelity over 2/3 classical teleportation limit. In addition, the QHB protocol is proposed for source station and destination station realizing handshake. We define the process of the protocol to illustrate how the protocol works. Based on the fidelity function, we analyze the feasibility of the QHB and verify that the QHB can work well within the maximal retry times in communication protocol. Compared with the unidirectional QHB, the bidirectional QHB has less system average delay.

Bidirectional Quantum Teleportation by Using Five-qubit Cluster State

We propose a scheme for bidirectional quantum teleportation by using a five-qubit cluster state. In our scheme, Alice can transmit an arbitrary two-qubit entangled state to Bob and at the same time Bob can teleport an arbitrary single-qubit state to Alice.