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arXiv · 2306.17273

Quantum sensing via magnetic-noise-protected states in an electronic spin dyad

Carlos A. Meriles·Pablo R. Zangara·Daniela Pagliero
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Abstract

Extending the coherence lifetime of a qubit is central to the implementation and deployment of quantum technologies, particularly in the solid-state where various noise sources intrinsic to the material host play a limiting role. Here, we theoretically investigate the coherent spin dynamics of a hetero-spin system formed by a spin S=1 featuring a non-zero crystal field and in proximity to a paramagnetic center S'=1/2. We capitalize on the singular energy level structure of the dyad to identify pairs of levels associated to magnetic-field-insensitive transition frequencies, and theoretically show that the zero-quantum coherences we create between them can be remarkably long-lived. Further, we find these coherences are selectively sensitive to 'local' - as opposed to 'global' - field fluctuations, suggesting these spin dyads could be exploited as nanoscale gradiometers for precision magnetometry or as probes for magnetic-noise-free electrometry and thermal sensing.

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Carlos A. Meriles, Pablo R. Zangara, Daniela Pagliero. 2023-06-29. Quantum sensing via magnetic-noise-protected states in an electronic spin dyad. https://arxiv.org/abs/2306.17273

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