Design and simulations of efficient quantum light sources

The single-photon source capable of emitting single indistinguishable photons on demand represents a key component in quantum information applications. Photons generated using parametric downconversion have shown high degree of indistinguishability, but the probabilistic nature of this process makes them unsuitable for upscaling to experiments involving more than a handful of photons. An attractive alternative is a deterministic source based on a two-level system in a solid-state environment. However, for a quantum emitter in a bulk material, most of the light is emitted into the substrate and the collection efficiency is only a few percent. In this presentation, I will give an overview of strategies for engineering of the photonic environment to increase the efficiency towards unity. Sources based on the micropillar geometry and the photonic nanowire geometry have demonstrated efficiencies above 0.7 and will be discussed in detail.