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arXiv · 2507.18387

Observation of period doubling and higher multiplicities in a driven single-spin system

Dhruv Deshmukh·Raúl B. González·Roberto Sailer·Fedor Jelezko·Ressa S. Said·Joachim Ankerhold
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Abstract

One of the prime features of quantum systems strongly driven by external time-periodic fields is the subharmonic response with integer multiples of the drive period $k\, T_d$ due to long-lived interference. Here, we demonstrate experimentally, based on a careful theoretical analysis, period doubling and higher multiplicities ($k=2,\ldots 5$) for one of the most fundamental systems, namely, an individual spin $1/2$. Nitrogen-vacancy centers in diamond support sufficiently stable coherent dynamics owing to long coherence times and allow for optical addressability of their spin states. This allows to monitor coherent period $k$-tupling oscillations over a broad set of driving parameters in the vicinity of the ideal manifolds. In this domain, superimposed low-frequency modulations serve as unique proxy for the approach toward period $k$-tupling.

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Dhruv Deshmukh, Raúl B. González, Roberto Sailer, Fedor Jelezko, Ressa S. Said, Joachim Ankerhold. 2025-07-24. Observation of period doubling and higher multiplicities in a driven single-spin system. https://doi.org/10.1103/wj1t-vk39

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