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.
@article{arxiv.2308.11710,
title = {Magnon-mediated qubit coupling determined via dissipation measurements},
author = {Masaya Fukami and Jonathan C. Marcks and Denis R. Candido and Leah R. Weiss and Benjamin Soloway and Sean E. Sullivan and Nazar Delegan and F. Joseph Heremans and Michael E. Flatté and David D. Awschalom},
journal= {arXiv preprint arXiv:2308.11710},
year = {2024}
}