Efficient generation of nitrogen-vacancy center inside diamond with shortening of laser pulse duration

Abstract

We investigated the effect of laser pulse duration on nitrogen-vacancy (NV) center generation inside a single crystal diamond. We compared pulse durations of 40 fs (femtosecond laser) and 1 ps (picosecond laser). We found that in both cases, ensemble NV centers could be generated inside the diamond. However, the maximum photoluminescence intensity of the NV center without graphitization for the 40 fs duration was higher than that for the 1 ps duration. This indicated that the femtosecond laser was harder to graphitize diamond and could generate more NV centers without graphitization. This difference may be due to the difference in the photo-absorption process and the resulting lattice dynamics.