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arXiv · 2408.14318

Blueprint for Diamond Magnetometry: Unraveling Quantum Dephasing of Nitrogen-Vacancy Center Ensembles in Diamond

Jixing Zhang·Cheuk Kit Cheung·Michael Kuebler·Magnus Benke·Mathis Brossaud·Andrej Denisenko·Ruoming Peng·Jens Anders·Emilio Corcione·Cristina Tarín Sauer·Andrew M. Edmonds·Matthew Markham·Kazuo Nakamura·Hitoshi Sumiya·Shinobu Onoda·Junichi Isoya·Chen Zhang·Joerg Wrachtrup
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Abstract

Diamonds with nitrogen-vacancy (NV) center ensembles are one of the most promising solid-state quantum platforms for various sensing applications. The combination of a long spin dephasing time ($T_2^*$) and a high NV center concentration is crucial for pushing the sensitivity limits. In this work, we propose a systematic measurement approach to quantify the electron spin dephasing in NV center ensembles and analyze the contributions of various sources to the dephasing time, including NV-NV interactions, strain and electric field distributions, $^{13}$C nuclear spins, and P1 electron spins. Our method is validated using a series of high-performance diamond samples, providing a comprehensive understanding of dephasing mechanisms and revealing correlations between NV concentration and different dephasing sources. Based on these insights, we further evaluate and propose strategies to improve the achievable sensitivity limits for DC magnetic field measurements.

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Jixing Zhang, Cheuk Kit Cheung, Michael Kuebler, Magnus Benke, Mathis Brossaud, Andrej Denisenko, Ruoming Peng, Jens Anders, Emilio Corcione, Cristina Tarín Sauer, Andrew M. Edmonds, Matthew Markham, Kazuo Nakamura, Hitoshi Sumiya, Shinobu Onoda, Junichi Isoya, Chen Zhang, Joerg Wrachtrup. 2024-08-26. Blueprint for Diamond Magnetometry: Unraveling Quantum Dephasing of Nitrogen-Vacancy Center Ensembles in Diamond. https://arxiv.org/abs/2408.14318

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