Dynamic-nuclear-polarization-weighted spectroscopy of multi-spin electronic-nuclear clusters

Abstract

Nuclear spins and paramagnetic centers in a solid randomly group to form clusters featuring nearly-degenerate, hybrid states whose dynamics are central to processes involving nuclear spin-lattice relaxation and diffusion. Their characterization, however, has proven notoriously difficult mostly due to their relative isolation and comparatively low concentration. Here, we combine field-cycling experiments, optical spin pumping, and variable radio-frequency (RF) excitation to probe transitions between hybrid multi-spin states formed by strongly coupled electronic and nuclear spins in diamond. Leveraging bulk nuclei as a collective time-integrating sensor, we probe the response of these spin clusters as we simultaneously vary the applied magnetic field and RF excitation to reconstruct multi-dimensional spectra. We uncover complex nuclear polarization patterns of alternating sign that we qualitatively capture through analytical and numerical modeling. Our results unambiguously expose the impact that strongly-hyperfine-coupled nuclei can have on the spin dynamics of the crystal, and inform future routes to spin cluster control and detection.

References in corpus (9)

• Optically addressable molecular spins for quantum information processing
• Bulk Nuclear Polarization Enhanced at Room-Temperature by Optical Pumping
• Dynamic nuclear polarization and spin-diffusion in non-conducting solids
• Multi-spin-assisted optical pumping of bulk 13C nuclear spin polarization in diamond
• 13C dynamic nuclear polarization in diamond via a microwave-free 'integrated' cross effect
• Optically Detected Cross-Relaxation Spectroscopy of Electron Spins in Diamond
• Magnetic-field-induced delocalization in hybrid electron-nuclear spin ensembles
• Microwave-free dynamic nuclear polarization via sudden thermal jumps
• Nuclear spin temperature reversal via continuous radio-frequency driving