A scheme is proposed for cyclic-controlled quantum operation teleportation (CCQOT) for three sides with EPR and cluster states. Under the control of David, Alice can implement an unknown single-qubit unitary operation on the remote Bob’s quantum system, while Bob can execute a single-qubit unitary operation on Charlie’s quantum system and Charlie can also perform an unknown single-qubit unitary operation on Alice’s quantum system. Our scheme can be generalized to [Formula: see text]) agents involved in the cycle to realize the transmission of single-qubit operations. Moreover, by replacing the quantum channels, we can change the cyclic direction of controlled qunatum operation teleportation (CQOT) from clockwise to counterclockwise. In addition, we discuss our scheme in four types of noisy environments (amplitude-damping, phase-damping, bit-flip and phase-flip noisy environment), and use fidelity to analyze the amount of information lost in the process of CCQOT due to noise. The results show that the fidelity is determined by decoherence rate and amplitude parameters of the final state.
A scheme is proposed for cyclic-controlled quantum operation teleportation (CCQOT) for three sides with EPR and cluster states. Under the control of David, Alice can implement an unknown single-qubit unitary operation on the remote Bob’s quantum system, while Bob can execute a single-qubit unitary operation on Charlie’s quantum system and Charlie can also perform an unknown single-qubit unitary operation on Alice’s quantum system. Our scheme can be generalized to [Formula: see text]) agents involved in the cycle to realize the transmission of single-qubit operations. Moreover, by replacing the quantum channels, we can change the cyclic direction of controlled qunatum operation teleportation (CQOT) from clockwise to counterclockwise. In addition, we discuss our scheme in four types of noisy environments (amplitude-damping, phase-damping, bit-flip and phase-flip noisy environment), and use fidelity to analyze the amount of information lost in the process of CCQOT due to noise. The results show that the fidelity is determined by decoherence rate and amplitude parameters of the final state.
A new concept of bidirectional quantum operation teleportation (BQOT) is proposed, which is essentially a union of the idea of quantum operation teleportation (QOT) and bidirectional quantum teleportation (QT). This means that Alice can transmit an unknown single-qubit unitary operation [Formula: see text] on the remote Bob’s quantum system; and at the same time, Bob can also transmit an arbitrary single-qubit unitary operation [Formula: see text] on Alice’s quantum system. In this paper, we present three BQOT schemes via different quantum channels. Furthermore, using these quantum channels, we investigate the BQOT in noisy environments, such as phase-damping noise and amplitude-damping noise. We considered the influence of the noises on the process of these three BQOT protocols through analytical derivation of the fidelity. Moreover, these three schemes are amply compared with each other from five aspects, i.e. quantum resource consumption, operation complexity, classical resource consumption, success probability and efficiency. It is found that these schemes can be realized deterministically and the first scheme is better than the other two schemes.
The quantum teleportation is an emerging communication technology based on the principles of quantum mechanics. It utilizes the properties of quantum entanglement and quantum superposition to achieve secure transmission of information. Most of the current quantum teleportation protocols are analyzed under ideal environment, and merely realized the transmission of either single or two particle unknown quantum states between two participants. In this paper, by using eleven entangled quantum states as a quantum channel, we propose a cyclic and asymmetric novel protocol for four participants. The communication task is achieved by employing GHZ state measurement (GHZ), single-qubit measurement (SM), and unitary operations (UO) as the foundation of this protocol. Analysis demonstrates that the success probability of the proposed protocol can reach 100%. Furthermore, considering that in actual production environments, it is difficult to avoid the occurrence of noise in quantum channels, this paper also analyzes the changes in fidelity in two types of noisy scenarios: bit-flip noise, phase-flip noise. Showing that communication quality only depends on the amplitude parameters of the initial state and decoherence rate. Finally, we give a comparison with previous similar schemes in terms of achieved method and intrinsic efficiency, which illustrates the superiority of our protocol.
In this paper, a scheme for cyclic hybrid double-channel quantum communication is proposed by using the product state of three Bell states and three Greenberger-Horne-Zeilinger (GHZ) states as the quantum channel. It shows that Alice teleports a single-qubit state to Bob and prepares a single-qubit state for Charlie, Bob teleports a single-qubit state to Charlie and prepares a single-qubit state for Alice, while Charlie teleports a single-qubit state to Alice and prepares a single-qubit state for Bob. The quantum channel is constructed by using Hadamard (H) and Controlled-NOT (CNOT) operations. Participants reconstruct the desired states by performing Bell-state measurements, single-qubit measurements, and unitary transformations. Compared with existing schemes, this new scheme improves the efficiency and capacity of quantum communication because it constructs a cyclic and bidirectional quantum communication and simultaneously supports two communication protocols, quantum teleportation and remote state preparation. Only single-qubit measurements, two-qubit measurements, and basic unitary transformations are utilized in the scheme, so our operation complexity is lower than others. Thus, the scheme is likely to be implemented through physical experiments in the future. Besides this, we discuss the impact of noisy environments (amplitude-damping, phase-damping noise, bit-flip noise, and phase-flip noise) in the scheme and calculate the fidelities of the output states. It is demonstrated that the fidelities only depend on the coefficients of the initial state and the decoherence rate.
In this paper, two schemes for cyclic quantum teleportation (CQT) and cyclic controlled quantum teleportation (CCQT) in a high-dimension system are proposed. In the first scheme, three distant agents, Alice, Bob and Charlie, are not only the senders but also the receivers, and via the six-qutrit entangled state as the quantum channel, Alice can transfer her quantum information to Bob, at the same time, Bob can transfer his quantum information to Charlie and Charlie can transfer his quantum information to Alice. While for the second scheme, there is one controller David, and only with the help of him can the teleportation be accomplished via the seven-qutrit entangled state as the quantum channel. These schemes can be generalized to realize the teleportation with [Formula: see text] agents. Furthermore, the resource consumption and feasibility of the schemes are investigated at the end of the paper.
In this paper, by using eleven entangled quantum states as a quantum channel, we propose a cyclic and asymmetric novel protocol for four participants in which both Alice and Bob can transmit two-qubit states, and Charlie can transmit three-qubit states with the assistance of the supervisor David, who provides a guarantee for communication security. This protocol is based on GHZ state measurement (GHZ), single-qubit measurement (SM), and unitary operations (UO) to implement the communication task. The analysis demonstrates that the success probability of the proposed protocol can reach 100%. Furthermore, considering that in actual production environments, it is difficult to avoid the occurrence of noise in quantum channels, this paper also analyzes the changes in fidelity in four types of noisy scenarios: bit-flip noise, phase-flip noise, bit-phase-flip noise, and depolarizing noise. Showing that communication quality only depends on the amplitude parameters of the initial state and decoherence rate. Additionally, we give a comparison with previous similar schemes in terms of achieved method and intrinsic efficiency, which illustrates the superiority of our protocol. Finally, in response to the vulnerability of quantum channels to external attacks, a security analysis was conducted, and corresponding defensive measures were proposed.
Following the work of Chen et al. [Quantum Inf. Process. 16, 201 (2017)] and Zhang [Mod. Phys. Lett. A 34, 1950290 (2019)], we propose a scheme for cyclic quantum teleportation (CYQT) in which three participants Alice, Bob and Charlie can teleport three arbitrary single-qubit information states cyclically among themselves by using GHZ-like states. Chen et al. and Zhang proposed schemes for CYQT and bidirectional quantum teleportation (BQT) involving three participants, respectively. In the scheme of Chen et al., the quantum teleportation (QT) can be realized successfully between any two participants without the help of third participants and in Zhang’s scheme, two unknown single-qubit states are teleported bidirectionally between two participants with the help of a third participant. On the other hand, in our proposed scheme, all the three participants are controller as well as sender and receiver. The teleportation processes Alice [Formula: see text] Bob, Bob [Formula: see text] Charlie and Charlie [Formula: see text] Alice are controlled by Charlie, Alice and Bob, respectively, and hence the CYQT could not be realized successfully without the cooperation of all three participants. If any one participant denies to cooperate with other two participants, then the CYQT cannot be realized successfully.