We investigated the coupling of single InGaAs quantum dots (QD) to localised modes of two-dimensional photonic crystal (PC) microcavities. The goal was to realise an efficient single photon turnstile device using cavity quantum electrodynamic phenomena in a solid state system. Single QDs were embedded in PCs that strongly altered and spatially redistributed the spontaneous emission (SE) due to the appearance of a photonic band gap. This results in efficient single photon generation with photon extraction efficiencies up to 25%. Single photon sources with high brightness and, an enhanced SE rate, were realised by PC microcavities. Single QDs coupled to localised cavity modes exhibited Purcell enhanced single photon emission with a SE rate up to 4/ns. Non-resonant coupling between the detuned QDs and the cavity mode was found, lowering the purity of single photon emission. We suggest combining microcavities and lateral electric fields to realise an efficient source of entangled photon pairs.
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