Optical coherence of implanted silicon vacancy centers in thin diamond membranes

We report the fabrication and optical characterization of thin diamond membranes implanted with negatively charged silicon vacancy (SiV^-) centers. The variations in the membrane thickness enable the experimental study of optical coherence of SiV^- centers as the membrane thickness is varied from 100 nm to 1100 nm. Photoluminescence excitation spectroscopy at low temperature shows that most of the SiV^- centers in these membranes feature an optical linewidth ranging between 200 and 300 MHz. Furthermore, there is no discernable dependence of the optical linewidth on the membrane thickness for membranes as thin as 100 nm, indicating the feasibility of incorporating SiV^- centers in a varity of diamond nanostructures and still maintaining the excellent optical coherence of these color centers.