Silicon-Vacancy Color Centers in Nanodiamonds: Cathodoluminescence Imaging Markers in the Near Infrared

Nanodiamonds doped with silicon-vacancy (Si-V) color centers are shown to be a promising candidate for cathodoluminescence (CL) imaging at the nanoscale, providing bright, non-bleaching, narrow-linewidth emission at wavelengths within the near-IR window of biological tissue. CL emission intensity from negative charge-state Si-V centers is greatly enhanced by increasing the nitrogen concentration during nanodiamond growth.