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arXiv · 2103.12742

Probing many-body dynamics in a two dimensional dipolar spin ensemble

Emily J. Davis·Bingtian Ye·Francisco Machado·Simon A. Meynell·Weijie Wu·Thomas Mittiga·William Schenken·Maxime Joos·Bryce Kobrin·Yuanqi Lyu·Zilin Wang·Dolev Bluvstein·Soonwon Choi·Chong Zu·Ania C. Bleszynski Jayich·Norman Y. Yao
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Abstract

The most direct approach for characterizing the quantum dynamics of a strongly-interacting system is to measure the time-evolution of its full many-body state. Despite the conceptual simplicity of this approach, it quickly becomes intractable as the system size grows. An alternate framework is to think of the many-body dynamics as generating noise, which can be measured by the decoherence of a probe qubit. Our work centers on the following question: What can the decoherence dynamics of such a probe tell us about the many-body system? In particular, we utilize optically addressable probe spins to experimentally characterize both static and dynamical properties of strongly-interacting magnetic dipoles. Our experimental platform consists of two types of spin defects in diamond: nitrogen-vacancy (NV) color centers (probe spins) and substitutional nitrogen impurities (many-body system). We demonstrate that signatures of the many-body system's dimensionality, dynamics, and disorder are naturally encoded in the functional form of the NV's decoherence profile. Leveraging these insights, we directly characterize the two-dimensional nature of a nitrogen delta-doped diamond sample. In addition, we explore two distinct facets of the many-body dynamics: First, we address a persistent debate about the microscopic nature of spin dynamics in strongly-interacting dipolar systems. Second, we demonstrate direct control over the correlation time of the many-body system. Finally, we demonstrate polarization exchange between NV and P1 centers, opening the door to quantum sensing and simulation using two-dimensional spin-polarized ensembles.

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Emily J. Davis, Bingtian Ye, Francisco Machado, Simon A. Meynell, Weijie Wu, Thomas Mittiga, William Schenken, Maxime Joos, Bryce Kobrin, Yuanqi Lyu, Zilin Wang, Dolev Bluvstein, Soonwon Choi, Chong Zu, Ania C. Bleszynski Jayich, Norman Y. Yao. 2021-03-23. Probing many-body dynamics in a two dimensional dipolar spin ensemble. https://doi.org/10.1038/s41567-023-01944-5

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