Light Emission of Single Emitters in 3-dimensional Photonic Crystals

• Applicant: Professor Dr. Frank Cichos
• Subject Area: Experimental Condensed Matter Physics
• Term: from 2006 to 2013
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 24778895

One of the distinct properties of photonic crystals is their influence on the photoluminescence of embedded emitters. Photonic crystals can enhance or inhibit spontaneous emission due to a modification of the vacuum fluctuations of the electromagnetic field. They can redistribute emitted photons spatially and spectrally due to an anisotropic light propagation inside the photonic crystal. However, all of these properties depend on the local position of the emitter inside the photonic crystal and further its emission wavelength. Measurements on ensembles of emitters mix all these local effects, average over large spectral regions and therefore make a detailed investigation of the photonic crystal complicated. The novel experimental approach of this project is to remove the ensemble average and to probe the local density of states in a photonic crystal with single quantum dots just at one specific site and in a narrow frequency region. For this purpose defocused wide-field fluorescence microscopy will be employed to study the anisotropic light propagation in photonic crystals be means of single point like emitters. This will allow for the first time a spatially and frequency selective study of the variation of the local density of states in a photonic crystal and is further a direct step to control the emission of single photon sources with the help of 3-dimensional photonic crystals.

• DFG Programme: Research Grants