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arXiv · 2509.01467

Optically detected nuclear magnetic resonance of coherent spins in a molecular complex

Evgenij Vasilenko·Vishnu Unni Chorakkunnath·Jeremias Resch·Nicholas Jobbitt·Diana Serrano·Philippe Goldner·Senthil Kumar Kuppusamy·Mario Ruben·David Hunger
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Abstract

Nuclear magnetic resonance (NMR) is a powerful tool for applications ranging from chemical analysis to quantum information processing. Achieving optical initialization and detection of molecular nuclear spins promises new opportunities - including improved NMR signals at low magnetic field, sensitivity down to the single-molecule level, and full access to atomically precise molecular architectures for quantum technologies. In this study, we report optical readout of coherently controlled nuclear spins in a europium-based molecular crystal. By harnessing ultra-narrow optical transitions, we achieve optical initialization and detection of nuclear spin states. Through radio-frequency driving, we address two nuclear quadrupole resonances, characterized by narrow inhomogeneous linewidths and a distinct correlation with the optical transition frequency. We implement Rabi oscillations, spin echo and dynamical decoupling techniques, achieving nuclear spin quantum coherence with a lifetime of up to 2 ms. These results highlight the capabilities of optically detected NMR (ODNMR) and underscore the potential of molecular nuclear spins for quantum information processing.

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Evgenij Vasilenko, Vishnu Unni Chorakkunnath, Jeremias Resch, Nicholas Jobbitt, Diana Serrano, Philippe Goldner, Senthil Kumar Kuppusamy, Mario Ruben, David Hunger. 2025-09-01. Optically detected nuclear magnetic resonance of coherent spins in a molecular complex. https://arxiv.org/abs/2509.01467

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