Tracking emission rate dynamics of nitrogen vacancy centers in nanodiamonds

Spontaneous emission from crystal centers is in uenced by both the photonic local density of states and non- radiative processes. Here we monitor the spontaneous emission of single nitrogen vacancy (NV) centers as their host diamond is reduced in size from a large monolithic crystal to a nanocrystal by successive cycles of oxidation. The size reduction induces a quenching of the NV radiative emission. New non-radiative channels lead to a decrease of the uorescence intensity and the excited state lifetime. In one case we observe the onset of blinking which may provide a route to understand these additional non-radiative decay channels.