Deterministic entanglement swapping of W states

TL;DR

This paper presents a deterministic protocol for swapping entanglement to generate shared W states between remote parties, improving reliability over probabilistic methods for quantum communication.

Contribution

It introduces a deterministic entanglement swapping protocol for W states, including a quantum circuit design and a purification method to enhance fidelity under noise.

Findings

Protocol achieves high-fidelity W state sharing

Purification improves robustness against noise

Simulations validate practical applicability

Abstract

In this paper, we propose a deterministic entanglement swapping protocol for generating a shared three-qubit W state between two remote parties. Our method offers a reliable alternative to existing probabilistic protocols for W state entanglement swapping, which is crucial for various quantum information processing tasks. We present a detailed quantum circuit design, implemented using the Qiskit simulator, that outlines the preparation of W states and the execution of joint measurements required for the entanglement swapping process. Furthermore, we analyze the effects of imperfect operations and noisy communication channels on the fidelity of the resulting shared W state. To address these challenges, we introduce a weak measurement-based purification method that enhances fidelity in the presence of amplitude damping. Through mathematical analysis and Qiskit simulations, we demonstrate the effectiveness of our proposed protocol, offering a practical solution for high-fidelity W state generation in real-world quantum communication scenarios.