Pablo Merino(Max-Plank Institute, Stuttgart, Germany)
Quantum systems like molecules or quantum dots cannot emit two photons at the same time which results in an antibunching of the emitted photon train and a dip in the photon-photon correlation function. Such single photon emitters are key elements for quantum cryptography and their application needs a perfect optical separation of neighboring emitters. This requires reproducible emitter distances typically above the optical diffraction limit and has imposed strong limitations on suitable structures and materials.