Color centers in diamond are point defects that fluoresce in the visible spectrum.  The most prominent point defect is the nitrogen-vacancy (NV) center, which gained interest in the quantum technology community due its outstanding capacity for the optical preparation and detection of its electron spin in ambient conditions 
at the single defect level.  However, besides the outstanding capacity, the NV is not a perfect candidate for all applications.

There are many more color centers in diamond, many of which are not as well understood as NV, but nevertheless offer better properties for some applications.  In this talk, I want to present you an overview of the work done on the negatively-charged silicon-vacancy (SiV) center in diamond.  The SiV center is currently gaining scientific interest predominantly due to its uniquely attractive optical spectrum.  The narrow zero-phonon line contains 70% of the emission, exhibits excellent spectral stability and offers almost lifetime limited linewidth at 4K.  Beyond applications as a single photon source and resource for quantum information processing and communication, these properties are ideal for examining fundamental interactions between light and single quantum emitters.

Mathias H. Metsch is a PHD student of Prof. Fedor Jelezko at the Institute of Quantum Optic at university Ulm.  He is part of a work group performing low temperature spectroscopy of single defects in diamond where he is mostly working on spin control in single silicon vacancy centers (SiV).