EQuAL Seminar: Taylor Morrison

Engineering Spins and Charges at the Solid-State Interface for Nanoscale Quantum Sensing

Nitrogen-vacancy (NV) centers in diamond are a promising platform for nanoscale NMR and EPR, but two key challenges remain: controllably immobilizing molecular targets at the diamond surface and producing dense, coherent NV ensembles within a few nanometers of those targets. First, we introduce a method using DNA origami as a nanoscale breadboard to assemble programmable 2D arrays of spin-bearing molecules, which are then deposited onto a bulk diamond crystal hosting proximal NV centers. By controlling the spacing and occupancy of spin sites on the origami, we achieve tunable spin density within each NV’s sensing volume, verified with incoherent NV magnetometry. Second, we demonstrate a charge-assisted defect engineering approach leveraging sulfur pre-doping to enhance near-surface NV formation. By modifying the vacancy charge state during annealing, we achieve up to a 15x increase in the N-to-NV conversion efficiency without compromising coherence. I’ll discuss how these techniques work, what we’ve learned, and what comes next.