Atomistic mechanism of perfect alignment of nitrogen-vacancy centers in diamond

Nitrogen-vacancy (NV) centers in diamond have attracted a great deal of attention because of their possible use in information processing and electromagnetic sensing technologies. We examined the atomistic generation mechanism for the NV defect aligned in the [111] direction of C(111) substrates. We found that N is incorporated in the C bilayers during the lateral growth arising from a sequence of kink propagation along the step edge down to [1¯1¯2]. As a result, the atomic configuration with the N-atom lone-pair pointing in the [111] direction is formed, which causes preferential alignment of NVs. Our model is consistent with recent experimental data for perfect NV alignment in C(111) substrates.