Ideal Controlled quantum teleportation, discovered theoretically by Karlsson and Bourennane, is a weird paradigm of nonlocal transplantation of probability-amplitudes of an arbitrary unknown generic information-qubit possessed by a sender (Alice) on a qubit preserved by a distantly located receiver (Bob) under control or cooperation by a third party (Charlie) via maximally entangled Greenberger-Horne-Zeilinger (GHZ) state employed as the quantum channel with local operation and classical communication. The GHZ state is a fragile quantum resource and extremely sensitive to inevitable noisy environment causing decoherence. It fuels, therefore, an imperatively pressing demand to strategize a scheme for noise-resistant control quantum teleportation. We revisit the ideal control quantum teleportation but with a noisy Greenberger-Horne-Zeilinger State in which each intertwining qubit suffers with differing noises and inequivalent levels, namely, bit-flip, amplitude-flip and phase-flip, i.e., asymmetric noise ambience. The controlling power, introduced by Li and Ghose, is invoked to assess the performance of the afore-described noisy strategy. It is seen that differing levels of noises breaks the classical bound of controlling power and, thereby, demonstrating the loosening authority of controller. Our findings suggest that to which extent of asymmetric noise ambience noisy control quantum teleportation is noise-tolerant.
Ideal Controlled quantum teleportation, discovered theoretically by Karlsson and Bourennane, is a weird paradigm of nonlocal transplantation of probability-amplitudes of an arbitrary unknown generic information-qubit possessed by a sender (Alice) on a qubit preserved by a distantly located receiver (Bob) under control or cooperation by a third party (Charlie) via maximally entangled Greenberger-Horne-Zeilinger (GHZ) state employed as the quantum channel with local operation and classical communication. The GHZ state is a fragile quantum resource and extremely sensitive to inevitable noisy environment causing decoherence. It fuels, therefore, an imperatively pressing demand to strategize a scheme for noise-resistant control quantum teleportation. We revisit the ideal control quantum teleportation but with a noisy Greenberger-Horne-Zeilinger State in which each intertwining qubit suffers with differing noises and inequivalent levels, namely, bit-flip, amplitude-flip and phase-flip, i.e., asymmetric noise ambience. The controlling power, introduced by Li and Ghose, is invoked to assess the performance of the afore-described noisy strategy. It is seen that differing levels of noises breaks the classical bound of controlling power and, thereby, demonstrating the loosening authority of controller. Our findings suggest that to which extent of asymmetric noise ambience noisy control quantum teleportation is noise-tolerant.
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.
A multiparty-controlled teleportation (M-CT) scheme for securely teleporting an arbitrary unknown single-qubit state by using generalised Greenberger-Horne-Zeilinger (GHZ) states is presented in this paper, i.e., a sender, Alice, transmits an arbitrary single-qubit state to a distant receiver, Bob, under approving by all N controllers Charliei(i = 1, 2, …, N) in a quantum communication network. It is proved feasibly and easily to realise by quantum entanglement. The security of proposed scheme is also discussed. We make sure of the security of the quantum channel between the parties by decoy states. This scheme also can be used to share a quantum secret information in quantum secret sharing.
In distributed quantum computing, quantum networks provide a potential infrastructure for long-range quantum information processing. Controlled quantum teleportation (CQT) is a key practically relevant protocol that can connect two parties on a network and enables a third party, the controller to allow or abort the secure teleportation of an arbitrary single-qubit state between the two parties. We investigate the robustness of a three-qubit GHZ resource under bit-flip, phase-flip, depolarizing, and amplitude-damping noise. Using the Kraus-operator formalism, we characterize the noisy resource through multipartite quantum discord, genuine multipartite concurrence (GMC), localizable entanglement (LE), and CQT fidelity. We also outline a proof-of-concept photonic implementation for preparing the three-qubit GHZ resource and realizing the CQT protocol, which could enable experimental investigation of the effects of noise. Our results show that bit-flip and amplitude-damping noise generally preserve useful mutipartite quantum correlations over broader noise parameter ranges. Interestingly, multipartite discord exhibits freezing under bit-flip noise over a finite parameter regime. Moreover, discord can persist beyond the sudden death of genuine multipartite entanglement, revealing the distinct robustness of nonclassical correlations. We further demonstrate that CQT fidelity which characterizes the performance of CQT can exceed the classical threshold even after GMC vanishes, while LE more closely reflects the operational usefulness of the noisy resource. These findings highlight the complementary roles of quantum correlations and entanglement in assessing the resilience of GHZ-based protocols.
Abstract In this paper quantum teleportation of an unknown quantum state via noisy maximally bipartite (Bell) and maximally tripartite (Greenberger–Horne–Zeilinger (GHZ)) entangled states are investigated. We suppose that one of the observers who would receive the sent state accelerates uniformly with respect to the sender. The interactions of the quantum system with its environment during the teleportation process impose noises. These (unital and nonunital) noises are: phase damping, phase flip, amplitude damping and bit flip. In expressing the modes of the Dirac field used as qubits, in the accelerating frame, the so-called single mode approximation is not imposed. We calculate the fidelities of teleportation, and discuss their behaviors using suitable plots. The effects of noise, acceleration and going beyond the single mode approximation are discussed. Although the Bell states bring higher fidelities than GHZ states, the global behaviors of the two quantum systems with respect to some noise types, and therefore their fidelities, are different.
In this paper, a novel protocol for asymmetric bidirectional controlled quantum teleportation (ABCQT) by using the nine-qubit entangled state as a quantum channel is proposed. Alice transmits an arbitrary three-qubit entangled state to Bob and at the same time, Bob transmits an arbitrary single-qubit entangled state to Alice under the permission of a third party as a controller. This protocol is based on the Hadamard (H) gates, controlled-not (CNOT) operations, appropriate unitary operations, and single-qubit Von Neumann measurements (SM) which are more efficient than multi-qubit joint measurements (JM). This scheme explicitly shows how the channel of nine-qubit entangled state prepares, and it is discussed in six types of noisy scenarios (amplitude-damping, phase-damping, bit-flip, phase-flip, bit-phase-flip, and depolarizing noisy scenarios). Then, we analytically derive the fidelities of the ABCQT process and show that they only depend on the amplitude parameter of the initial state and the decoherence noisy rate. Finally, compared with previous schemes, this scheme also shows remarkable advantages.
A general scheme for controlled teleportation of an arbitrary multi-qudit state with d -dimensional Greenberger–Horne–Zeilinger (GHZ) states is proposed. For an arbitrary m -qudit state, the sender Alice performs m generalized Bell-state projective measurements on her 2 m qudits and the controllers need only take some single-particle measurements. The receiver Charlie can reconstruct the unknown m -qudit state by performing some single-qudit unitary operations on her particles if she cooperates with all the controllers. As the quantum channel is a sequence of maximally entangled GHZ states, the intrinsic efficiency for qudits in this scheme approaches 100% in principle.