(45f) High-Temperature, High-Pressure Molecular Doping of Nanodiamond for Sensing Applications

The synthesis and manipulation of luminescent defects, known as color centers, created by ion implantation in diamond form the basis for emerging quantum technologies. However, the lattice damage and fragmentation of dopant moieties during ion implantation prevents the deterministic generation of polyatomic defects. Here, we present a new method to dope nanodiamond by first synthesizing a nanostructured amorphous carbon precursor containing the desired defect motif and then converting it to nanodiamond at high temperatures and high pressures. This methodology enables defect formation controlled by solution chemistry without ion implantation. To explore this bottom-up method for color center generation, we rationally generate silicon-vacancy defects in nanodiamond and investigate them for optical pressure metrology. In addition, we show that this process can generate noble gas defects within diamond from the typically-inactive argon pressure medium, which may explain the hysteresis effects observed in other high pressure experiments and the presence of noble gases in some meteoritic nanodiamonds. Our results illustrate a general method to produce color centers in nanodiamond for applications in quantum sensing and may enable the controlled generation of designer defects.