Nitrogen in Diamond

Nitrogen is ubiquitous in both natural and laboratory-grown diamond, but the number and nature of the nitrogen-containing defects can have a profound effect on the diamond material and its properties. An ever-growing fraction of the supply of diamond appearing on the world market is now lab-grown. Here, we survey recent progress in two complementary diamond synthesis methods – high pressure high temperature (HPHT) growth and chemical vapour deposition (CVD), how each is allowing ever more precise control of nitrogen incorporation in the resulting diamond, and how the diamond produced by either method can be further processed (e.g. by implantation and/or annealing) to achieve a particular outcome or property. The burgeoning availability of diamond samples grown under well-defined conditions has also enabled huge advances in the characterization and understanding of nitrogen-containing defects in diamond – alone, and in association with vacancies, hydrogen and transition metal atoms. Amongst these, the negatively charged nitrogen-vacancy (NV) defect in diamond is attracting particular current interest on account of the many new and exciting opportunities it offers for, e.g., quantum technologies, nanoscale magnetometry and biosensing.