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arXiv · 2608.20742

Hybrid dynamical decoupling and coherent driving for high-fidelity nuclear-spin control in diamond

Jiwon Jeon·Donghun Jung·Eunsang Lee·Junghyun Lee
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Abstract

Nitrogen-vacancy (NV) centers in diamond provide room-temperature electron-nuclear spin registers for quantum sensing and quantum information processing, with surrounding 13C nuclear spins serving as long-lived quantum memories. However, coherent control of large nuclear-spin registers is limited by finite electron-spin coherence and spectral addressability. Existing approaches follow two complementary strategies: dynamical-decoupling (DD) gates exploit filter-function resonances to realize selective conditional evolution but permit only discrete rotation angles, whereas dynamical-decoupling radio-frequency (DDrf) control restores continuous tunability at the cost of stringent hyperfine-geometry and RF-power requirements. Here, we introduce hybrid dynamical-decoupling and radio-frequency (H-DDrf) control, which preserves the DD-induced conditional evolution and employs a geometrically phase-matched RF drive to complete the target operation. This approach reduces both RF power and gate duration while maintaining high-fidelity control, thereby expanding the accessible 13C nuclear-spin register for room-temperature NV-based quantum memories and quantum processors.

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Jiwon Jeon, Donghun Jung, Eunsang Lee, Junghyun Lee. 2026-08-21. Hybrid dynamical decoupling and coherent driving for high-fidelity nuclear-spin control in diamond. https://arxiv.org/abs/2608.20742

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