Electron paramagnetic resonance of the N2V−defect in N15-doped synthetic diamond

Nitrogen is the dominant impurity in the majority of natural and synthetic diamonds, and the family of nitrogen vacancy-type (NnV) defects are crucial in our understanding of defect dynamics in these diamonds. A significant gap is the lack of positive identification of N2V−, the dominant charge state of N2V in diamond that contains a significant concentration of electron donors. In this paper, we employ isotopically-enriched diamond to identify the EPR spectrum associated with 15 N2V− and use the derived spin Hamiltonian parameters to identify 14N2V− in a natural isotopic abundance sample. The electronic wave function of the N2V− ground state and previous lack of identification is discussed. The N2V− EPR spectrum intensity is shown to correlate with the H2 optical absorption over an order of magnitude in concentratio