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arXiv · 2311.18181

Observing coherence in an incoherent paramagnetic nitrogen spin bath

R. M. Goldblatt·A. M. Martin·A. A. Wood
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Abstract

The unpolarized spin environment surrounding a central spin qubit is typically considered as an incoherent source of dephasing, however, precise characterization and control of the spin bath can yield a resource for storing and sensing with quantum states. In this work, we use nitrogen-vacancy (NV) centers in diamond to measure the coherence of optically-dark paramagnetic nitrogen defects (P1 centers) and detect coherent interactions between the P1 centers and a local bath of $^{13}$C nuclear spins. The dipolar coupling between the P1 centers and $^{13}$C nuclear spins is identified by signature periodic collapses and revivals in the P1 spin coherence signal. We then demonstrate, using a range of dynamical decoupling protocols, that the probing NV centers and the P1 spins are coupled to independent ensembles of $^{13}$C nuclear spins. Our work illustrates how the optically-dark P1 spins, despite being unpolarized, can be used to extract information from their local environment and offers new insight into the interactions within a many-body system.

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R. M. Goldblatt, A. M. Martin, A. A. Wood. 2023-11-30. Observing coherence in an incoherent paramagnetic nitrogen spin bath. https://arxiv.org/abs/2311.18181

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