Optically functionalized nanoparticles are an ideal structure for a variety of research fields ranging from biophotonics to quantum optics. The research in the group concentrates on multifunctional photonic nanoparticles. Among those particles are diamond nanocrystals and carbon dots as well as dif
- Diamond nanoparticles
Few nanometer sized diamond particles can be produced either by shock synthesis or milling. While explosion grown diamond nanoparticles can be as small as 2-4nm milled nanodiamonds only recently have reached single digit size. Diamond nanoparticles are doped in a similar fashion than bulk diamond. Currently reports on nanodiamond containing different color centers are available. However, only nitrogen-vacancy (NV) doped nanodiamonds are available in sizeable quantities so far. The photophysics of defects in nanodiamonds has been studied. NV defects prove to be photostable in few nm sized crystals. However, there are reports on blinking behavior in very small nanoparticles. Photostability as well as spin properties in small nanodiamonds are subject of current research.
- YAG nanocrystals
The production of small diamond nanoparticles with versatile surface as well as surface functionality will be a future key challenge. ferently doped YAG nanocrystals.
Production and characterization of color centers in diamond material. Color center could be generated from diamond material with single substitutional nitrogen atoms by electron irradiation followed by thermal annealing. The standard diamond material made by HPHT synthesis with single substitutional nitrogen atoms (diamond material type Ib) is colored yellow, the green diamonds are irradiated material with high concentration of vacancies and the purple diamonds are irradiated and annealed material with high concentration of negatively charged NV-centers.