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arXiv · 2308.11710

Magnon-mediated qubit coupling determined via dissipation measurements

Masaya Fukami·Jonathan C. Marcks·Denis R. Candido·Leah R. Weiss·Benjamin Soloway·Sean E. Sullivan·Nazar Delegan·F. Joseph Heremans·Michael E. Flatté·David D. Awschalom
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Abstract

Controlled interaction between localized and delocalized solid-state spin systems offers a compelling platform for on-chip quantum information processing with quantum spintronics. Hybrid quantum systems (HQSs) of localized nitrogen-vacancy (NV) centers in diamond and delocalized magnon modes in ferrimagnets-systems with naturally commensurate energies-have recently attracted significant attention, especially for interconnecting isolated spin qubits at length-scales far beyond those set by the dipolar coupling. However, despite extensive theoretical efforts, there is a lack of experimental characterization of the magnon-mediated interaction between NV centers, which is necessary to develop such hybrid quantum architectures. Here, we experimentally determine the magnon-mediated NV-NV coupling from the magnon-induced self-energy of NV centers. Our results are quantitatively consistent with a model in which the NV center is coupled to magnons by dipolar interactions. This work provides a versatile tool to characterize HQSs in the absence of strong coupling, informing future efforts to engineer entangled solid-state systems.

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Masaya Fukami, Jonathan C. Marcks, Denis R. Candido, Leah R. Weiss, Benjamin Soloway, Sean E. Sullivan, Nazar Delegan, F. Joseph Heremans, Michael E. Flatté, David D. Awschalom. 2023-08-22. Magnon-mediated qubit coupling determined via dissipation measurements. https://doi.org/10.1073/pnas.2313754120

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