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arXiv · 2006.07736

Magnetic-field-induced delocalization in hybrid electron-nuclear spin ensembles

Daniela Pagliero·Pablo R. Zangara·Jacob Henshaw·Ashok Ajoy·Rodolfo H. Acosta·Neil Manson·Jeffrey A. Reimer·Alexander Pines·Carlos A. Meriles
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Abstract

We use field-cycling-assisted dynamic nuclear polarization and continuous radio-frequency (RF) driving over a broad spectral range to demonstrate magnetic-field-dependent activation of nuclear spin transport from strongly-hyperfine-coupled 13C sites in diamond. We interpret our observations with the help of a theoretical framework where nuclear spin interactions are mediated by electron spins. In particular, we build on the results from a 4-spin toy model to show how otherwise localized nuclear spins must thermalize as they are brought in contact with a larger ancilla spin network. Further, by probing the system response to a variable driving field amplitude, we witness stark changes in the RF-absorption spectrum, which we interpret as partly due to contributions from heterogeneous multi-spin sets, whose 'zero-quantum' transitions become RF active thanks to the hybrid electron-nuclear nature of the system. These findings could prove relevant in applications to dynamic nuclear polarization, spin-based quantum information processing, and nanoscale sensing.

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Daniela Pagliero, Pablo R. Zangara, Jacob Henshaw, Ashok Ajoy, Rodolfo H. Acosta, Neil Manson, Jeffrey A. Reimer, Alexander Pines, Carlos A. Meriles. 2021-02-26. Magnetic-field-induced delocalization in hybrid electron-nuclear spin ensembles. https://doi.org/10.1103/physrevb.103.064310

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