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.
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.
The effects of distributing entanglement through the amplitude damping channel or the phase damping channel on the teleportation of a single-qubit state via the Greenberger–Horne–Zeilinger state and the W state are discussed. It is found that the average fidelity of teleportation depends on the type and rate of the damping in the channel. For the one-qubit affected case, the Greenberger–Horne–Zeilinger state is as robust as the W state, i.e., the same quantum information is preserved through teleportation. For the two-qubit affected case, the W state is more robust when the entanglement is distributed via the amplitude damping channel; if the entanglement is distributed via the phase damping channel, the W state is more robust when the noisy parameter is small while the Greenberger–Horne–Zeilinger state becomes more robust when it is large. For the three-qubit affected case, the Greenberger–Horne–Zeilinger state is more robust than the W state.
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.
Abstract This study investigates the effect of noise on two-qubit quantum teleportation through a four-qubit entangled channel theoretically. Therefore, in this study a comparison of two states of teleportation through ideal and noisy channel was carried out. The noisy channel can have the effect of bit-flip channel and phase-flip channel. From these two effects, it is found that the channel transforms in-to a mixed state. If the noise is neglected, the channel is pure state. Then, this channel is measured and fidelity is calculated. The fidelity of an ideal environment is 1. This indicates that the teleportation was successfully sent and at the same time confirms the teleportation behavior under ideal conditions. In noisy environments, fidelity can be less than 1. Two factors in noisy environment that affect fidelity are noise factor (p) and the orginal parameter states (transmission coefficients). In this calculation, for the bit flip noise, we observed that as the values of the coefficient values of transmitted state increase, the fidelity value increases. Meanwhile, for the phase flip noise, we observed that as the values of the coefficient values of transmitted state increase, the fidelity value decreases.
Quantum teleportation in the presence of noisy channels acting on a bipartite resource state is considered. We consider a family of generalized noisy channels that continuously connect the amplitude damping and the dephasing channels, encompassing a wide family of in-between scenarios, to delve into the relation between the teleportation success and the amount of three- and four-partite entanglement (distributed among the qubits of the resource state and those representing local environments) generated during the evolution. Our analysis reveals that for a fixed entanglement of the resource state, the channels that better protect the teleportation fidelity against the detrimental effects of noise are those that generate higher amounts of (Greenberger-Horne-Zeilinger--type) multipartite entanglement. This suggests that the dynamically induced multipartite correlations may serve as an additional resource for teleportation and provides insight into the characterization of processes and of the type of induced entanglement according to their ability to assist the protocol.
Abstract Quantum communication is an integral part of quantum computing, where teleportation of a quantum state has gained significant attention from researchers. Many teleportation schemes have been introduced in the recent past. In this study, the authors compare the teleportation of a single‐qubit message among different entangled channels such as the two‐qubit Bell channel, three‐qubit GHZ channel, two/three‐qubit cluster states, a highly entangled five‐qubit state (Brown et al.) and the six‐qubit state (Borras et al.). The authors calculate and compare the quantum costs for these channels. The authors also study the effects of six noise models: bit‐flip noise, phase‐flip noise, bit‐phase‐flip noise, amplitude damping, phase damping and depolarising error. These noise models may affect the communication channel used for teleportation. An investigation of the variation of the initial state's fidelity is performed for the teleported state in the presence of the noise model. It is observed that the fidelity decreases in all the entangled channels as the noise parameter η increases in the range [0, 0.5] for all the noise models. The fidelity shows an upward trend in the Bell, GHZ and three‐qubit cluster state channels, as η varies in the range [0.5, 1.0] for all the noise models. However, in the rest of the three channels, the fidelity substantially decreases in the case of amplitude damping, phase damping and depolarising noise, and even it reaches zero for η = 1 in Brown et al. and Borras et al. channels.
Quantum teleportation plays a significant role in the field of quantum communication. This paper investigates quantum teleportation through a noisy environment by using GHZ state and non-standard W state as quantum channels. We analyze the efficiency of quantum teleportation by solving analytically a master equation in Lindblad form. Following the quantum teleportation protocol, we obtain the fidelity of quantum teleportation as a function of evolution time. The calculation results show that the teleportation fidelity using non-standard W is higher in comparison to GHZ state at the same evolution time. Moreover, we consider the efficiency of teleportation with weak measurements and reverse quantum measurement under amplitude damping noise. Our analysis suggests that the teleportation fidelity using non-standard W is also more robust to noise than GHZ state in the same conditions. Interestingly, we found that weak measurement and its reverse operation have no positive effect on the efficiency of quantum teleportation by using GHZ and non-standard W state in the amplitude damping noise environment. In addition, we also demonstrate the efficiency of quantum teleportation can be improved by making minor modifications to the protocol.