Fabrication of SiV centers inside nanodiamonds using ion implantation

Nanodiamonds containing color centers have been attracting attention as a hybrid system with nanophotonic devices to realize photonic quantum information devices such as highly efficient single photon sources. In various color centers, silicon vacancy (SiV) centers are especially interesting because of high photo-stability, high brightness, high Debye-Waller factor (about 70%), and lifetime-limited fluorescence linewidth. The nanodiamonds containing SiV centers have been usually fabricated by milling large nanodiamonds with SiV centers, which are synthesized by chemical vapor deposition (CVD). However, this milling method has an issue with the production yield. Here, we report on the fabrication of SiV centers inside nanodiamonds by direct implantation of Si ions, which allows the creation at a high production yield due to no requirement of the milling process. By implanting Si ions into nanodiamonds (median size of 25 nm), we fabricate SiV centers exhibiting a narrow linewidth of about 7 nm at room temperature. This linewidth is more than twice as narrow as previous reports on the implantation of Si ions into nanodiamonds.3rd IFQM