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arXiv · 2008.09541

Quantum sensing of a coherent single spin excitation in a nuclear ensemble

Daniel M. Jackson·Dorian A. Gangloff·Jonathan H. Bodey·Leon Zaporski·Clara Bachorz·Edmund Clarke·Maxime Hugues·Claire Le Gall·Mete Atatüre
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Abstract

The measurement of single quanta in a collection of coherently interacting objects is transformative in the investigations of emergent quantum phenomena. An isolated nuclear-spin ensemble is a remarkable platform owing to its coherence, but detecting its single spin excitations has remained elusive. Here, we use an electron spin qubit in a semiconductor quantum dot to sense a single nuclear-spin excitation (a nuclear magnon) with 1.9-ppm precision via the 200-kHz hyperfine shift on the 28-GHz qubit frequency. We demonstrate this single-magnon precision across multiple modes identified by nuclear species and polarity. Finally, we monitor the coherent dynamics of a nuclear magnon and the emergence of quantum correlations competing against decoherence. A direct extension of this work is to probe engineered quantum states of the ensemble including long-lived memory states.

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Daniel M. Jackson, Dorian A. Gangloff, Jonathan H. Bodey, Leon Zaporski, Clara Bachorz, Edmund Clarke, Maxime Hugues, Claire Le Gall, Mete Atatüre. 2020-08-21. Quantum sensing of a coherent single spin excitation in a nuclear ensemble. https://doi.org/10.1038/s41567-020-01161-4

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