Pagliero, DanielaZangara, PabloHenshaw, JacobAjoy, AshokAcosta, Rodolfo H.Manson, NeilReimer, Jeffrey A.Pines, AlexanderMeriles, Carlos A2023-03-012023-03-012469-9950http://hdl.handle.net/1885/286570We 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 four-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 multispin sets, whose zero-quantum transitions become RF active thanks to the hybrid electronnuclear nature of the system. These findings could prove relevant in applications to dynamic nuclear polarization, spin-based quantum information processing, and nanoscale sensing.D.P., J.H., and C.A.M. acknowledge support from the National Science Foundation through Grant No. NSF1903839, and from Research Corporation for Science Advancement through a FRED Award; they also acknowledge access to the facilities and research infrastructure of the NSF CREST IDEALS, Grant No. NSF-HRD-1547830. J.H. acknowledges support from CREST-PRF NSF-HRD 1827037. P.R.Z. and R.H.A. acknowledge financial support from CONICET (PIP-111122013010074 6CO), SeCyT-UNC (33620180100154CB), and ANPCYT (PICT-2014-1295).application/pdfen-AU© 2021 The authorsDiffusionDynamical phase transitionsPhase transitionsSpin dynamicsTransport phenomena202110.1103/PhysRevB.103.0643102021-12-26