A compact ensemble of high density nitrogen-vacancy (NV) centers in diamond is essential to sense various external fields with a high precision at the nanoscale. Here, defects in type IIa and type Ib diamonds induced by 28MeV electron irradiation at 77K were studied by combining the positron annihilation spectroscopy and first-principles calculations. It is shown that the electron irradiation at 77K can significantly enhance the NV center formation by directly converting 24% vacancies into the NV centers, indicating that it is an efficient way to produce the high density NV centers in the type Ib diamond.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)