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Chinese Physics Review

Divided-Qubit Noise-Tolerant Strategy for Bell State Preparation in Qiskit

Independent Researcher, Yang Daniel Ou, Wenming SUN

Published Dec 28, 2025• 0 citations

Abstract

This study focuses on achieving high-fidelity preparation of Bell states in depolarization noise environments. Based on Qiskit simulations, we propose a quantum-bit-by-quantum-bit noise-resistant strategy: applying dynamic decoupling to control qubits and implementing quantum error correction for target qubits. Experimental results demonstrate that this strategy maintains fidelity at 1. 0000 while significantly reducing the error rate from approximately 24% to 0. 4%, requiring only four additional quantum gate operations. The method achieves high-fidelity quantum entanglement with low complexity, showcasing significant practical value. As the standard form. of two-qubit maximum entanglement state, the Bell states are widely applied in critical tasks such as quantum teleportation, superdense coding, and quantum key distribution. However, real quantum systems inevitably interact with their environment, leading to quantum state decoherence and a significant decrease in the fidelity of the Bell state. Existing anti-jamming schemes mainly fall into two categories: dynamic decoupling through periodic pulse application to cancel noise, and quantum error correction through redundant encoding to fix errors. However, dynamic decoupling requires extremely high synchronization for multi-qubit systems, while quantum error correction necessitates additional auxiliary qubits, resulting in an exponential growth in circuit complexity.

DOI: 10.48014/cpr.20251029002

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