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arXiv · 2506.16974

Fidelity Relations in an Array of Neutral Atom Qubits -- Experimental Validation of Control Noise

Abstract

Noise is a hindering factor for current-era quantum computers. In this study, we experimentally validate the theoretical relationships between amplitude noise of the control signal and qubit state fidelity. The experiment comprises a 10x10 site optical tweezer array stochastically loaded with single rubidium-85 atoms. A global microwave field is used to manipulate the state of the hyperfine qubits. With precise control of the time-dependent amplitude of the microwave drive, we apply control signals featuring artificial noise. We systematically analyze the impact of various noise profiles on the fidelity distribution of the quantum states. The measured fidelities are compared against theoretical predictions made using the stochastic Schr\"odinger equation. Our results show a good agreement between the experimentally measured and theoretically predicted results. This validation is consequential, as the model provides critical information on noise identification and optimal control protocols in NISQ-era quantum systems.

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BibTeXRIS

Deon Janse van Rensburg, Robert de Keijzer, Rogier Venderbosch, Yuri van der Werf, Jesus del Pozo Mellado, Rianne Lous, Edgar Vredenbregt, Servaas Kokkelmans. 2025-06-20. Fidelity Relations in an Array of Neutral Atom Qubits -- Experimental Validation of Control Noise. https://doi.org/10.1103/66zh-yt9d

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