Near-surface spectrally stable nitrogen vacancy centres engineered in single crystal diamond.

A method for engineering thin (<100 nm) layers of homoepitaxial diamond containing high quality, spectrally stable, isolated nitrogen-vacancy (NV) centres is reported. The photoluminescence excitation linewidth of the engineered NVs are as low as 140 MHz, at temperatures below 12 K, while the spin properties are at a level suitable for quantum memory and spin register applications. This methodology of NV fabrication is an important step toward scalable and practical diamond based photonic devices suitable for quantum information processing.