Abstract The proposal of the quantum teleportation(QT) is to transfer an unknown quantum state from one place to another through local operations and classical communication. However, the efficiency of standard QT will be significantly reduced due to the influence of the inevitable noise in environments. In this work, we propose two schemes to improve the efficiency of the QT protocol when quantum channel is subjected to bit-flip or phase-flip noise. We find that the so-called more entanglement means low efficiency in the performance of the standard teleportation protocol, and the optimal fidelity is obtained only by using the appropriate unitary operation. Specially, we show that the optimal averaged fidelity to our schemes is always more than the best classically achievable fidelity 2/3. We also provide a physical explanation of the obtained conclusions and our results will be helpful for improving quantum communication with real implementation.
Abstract The proposal of the quantum teleportation(QT) is to transfer an unknown quantum state from one place to another through local operations and classical communication. However, the efficiency of standard QT will be significantly reduced due to the influence of the inevitable noise in environments. In this work, we propose two schemes to improve the efficiency of the QT protocol when quantum channel is subjected to bit-flip or phase-flip noise. We find that the so-called more entanglement means low efficiency in the performance of the standard teleportation protocol, and the optimal fidelity is obtained only by using the appropriate unitary operation. Specially, we show that the optimal averaged fidelity to our schemes is always more than the best classically achievable fidelity 2/3. We also provide a physical explanation of the obtained conclusions and our results will be helpful for improving quantum communication with real implementation.
In the domain of quantum communication, quantum teleportation (QT) emerges as a pivotal protocol, enabling the transmission of quantum states across significant distances. However, the ubiquitous presence of quantum noise inevitably affects this process, causing deviations in the teleported state from its intended configuration. This study proposes an innovative approach to mitigate noise error (bit-flip and phase-flip) and within quantum channels. The method involves implementing quantum gates between communicating parties, effectively diminishing the impact of these noise types on the entangled channel and enhancing QT efficacy in noise-prone environments. Experimental results demonstrate that noisy channel has low-fidelity 16.67% in bit flip noise and 68.60% in phase flip noise. The proposed noise mitigation quantum circuit attained the 100% fidelity.
Quantum teleportation is a useful communication protocol in quantum communication, which enables the transmission of quantum states over long distances. However, quantum noise inevitably affects quantum communication, resulting in the teleported state not being the ideal target state. In order to minimize the impact of quantum noise, we propose a new method to mitigate bit-flip and phase-flip noise of quantum channel in this paper. This method shares additional ancillary particles between the two parties of communication, which can effectively reduce the influence of bit-flip and phase-flip noise on the entangled channel, thereby improving the efficiency of quantum teleportation in noisy environments. We analyze the performance of the proposed method in detail through mathematical calculations. The results show that proposed scheme can resist the bit-flip and phase-flip noise with noise factor less than 0.5. When the noise factor is small, adding a small amount of auxiliary particles can greatly improve the fidelity of the output state: when the number of auxiliary particles increases to 5, the scheme can resist quantum noise with a noise factor less than or equal to 0.3, making fidelity of the output state is close to 1. When the noise factor is large, it is necessary to add more auxiliary particles to offset the influence of noise.
Abstract We propose a new protocol for quantum teleportation (QT) which adopts the Brown state as the quantum channel. This work focuses on the teleportation of a single unknown two-qubit state via a Brown state channel in an ideal environment. To validate the effectiveness of our proposed scheme, we conduct experiments by using the quantum circuit simulator Quirk. Furthermore, we investigate the effects of four noisy channels, namely, the phase damping noise, the bit-flip noise, the amplitude damping noise, and the phase-flip noise. Notably, we employ Monte Carlo simulation to elucidate the fidelity density under various noise parameters. Our analysis demonstrates that the fidelity of the protocol in a noisy environment is influenced significantly by the amplitude of the initial state and the noise factor.
Abstract Noiseless quantum channels are critical to share a pure maximally entangled state for performing an ideal teleportation protocol. However, in reality the shared entanglement severely degraded due to decoherence. In this paper, we propose a quantum teleportation channel protection scheme to enhance the teleportation fidelity in presence of decoherence. Before the entangled pair enters the decoherence channel, the weak measurement and flip operations are applied to transfer the qubit to a more robust state to the effects of the noise. After the decoherence channel the reversed flip operations and weak measurement reversal are applied to recover the initial state. We illustrate our protected teleportation scheme and compare it with a protocol based on weak measurement reversal. The numerical results show that the average teleportation fidelity of our proposed scheme can be significantly improved. Although the proposed entanglement protection scheme is probabilistic, after a successful entanglement transmission, we use the standard teleportation protocol which has probability one.
Achieving near-unity fidelity of Quantum Teleportation (QT) in a noisy environment is an essential requirement for its real-world applications. Towards this goal, we devise a distinctive protocol based on the timing of the sender Alice's Bell-basis measurement, synchronous with the suitably engineered structure of noise in the receiver Bob's wing, without requiring any knowledge or manipulation of Alice's local noise. For this purpose, to finally obtain the teleported states by performing the required unitary operations, Bob has to retain his qubits for only two particular Bell-basis outcomes communicated by Alice, whose corresponding reduced states have no dependence on the noise parameters in Alice's wing. Such postselection is crucial for enhancing the fidelity of the teleported state towards its ideal limit, while ensuring its full independence of Alice's noise. We formulate the specifics of our protocol in terms of a generic two-level quantum system, subjected to a general non-Markovian spin-boson model for dephasing noise. The proposed scheme is illustrated by using any pure maximally/non-maximally entangled state as well as a Werner-type mixed state as resource. In particular, using resource states having small values of entanglement measure, we show that the high fidelity of QT is achievable in the presence of noise. Further, using our scheme, considering even the local regime of Werner states, wherein the Bell-CHSH inequalities are not violated, we show that the QT fidelity in the presence of noise can be appreciably high.
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.