Hydrogen Incorporation in Diamond: The Nitrogen-Vacancy-Hydrogen Complex

We report the identification of the nitrogen-vacancy-hydrogen complex in a freestanding nitrogen-doped isotopically engineered single crystal diamond synthesized by chemical vapor deposition. The hydrogen atom is located in the vacancy of a nearest-neighbor nitrogen-vacancy defect and appears to be bonded to the nitrogen atom maintaining the trigonal symmetry of the center. The defect is observed by electron paramagnetic resonance in the negative charge state in samples containing a suitable electron donor (e.g., substitutional nitrogen $\mathrm{N}_S{}^0$).

Figure 1

EPR spectra observed in the ${}^{15}\mathrm{N}$ doped sample. The experimental spectra (upper curves) were recorded at room temperature, with the magnet field oriented along $⟨001⟩$, $⟨111⟩$, and $⟨110⟩$ directions. The simulations (lower curves) were obtained with the parameters given in the text.

Figure 2

(a) Room temperature EPR spectra ($B\parallel ⟨001⟩$) in ${}^{14}\mathrm{N}$ doped single crystal diamond grown by CVD; the strong central transition from the ${}^{14}\mathrm{N}_S{}^0$ center has been suppressed for clarity. (b) Room temperature EPR spectra in ${}^{14}\mathrm{N}$ doped single crystal diamond grown at high temperature/pressure using the solvent/catalyst process. Only the ${}^{14}\mathrm{N}_S{}^0$ center is observed, the central transition of which has been suppressed so that the ${}^{13}\mathrm{C}$ hyperfine satellites are visible. (c) Removal of all transitions associated with ${}^{14}\mathrm{N}_S{}^0$ in spectrum (a). (d) Simulation of ${}^{14}\mathrm{N}\mathrm{V}\mathrm{H}^{-}$ using parameters described in the text.