Light is an excellent system to implement quantum simulation or quantum computation tasks and the natural choice for connecting different nodes of a quantum networks.
Despite spectacular progresses in the last decade, optical quantum technologies today suffer from the low efficiency of currently used sources, most of them based on frequency conversion where only one percent of each pulse does indeed contain a single photon or an entangled photon pair.
We fabricate highly efficient integrated quantum light sources by inserting a single quantum dot in a microcavity.
Ultrabright single photon sources, where 60-80% of the pulse acutally contain a single photon are routinely fabricated using the in-situ lithography technique [Gazzano et. al. Nature Commun. 2013].
To obtain bright sources of entangled photon pairs, the quantum dot is inserted in coupled optical cavities [Dousse et. al, Nature 2010].
Recently, we have added an electrical control to the sources [Nowak et. al. Nature Commun. 2014] that allows tuning the source wavelength and obtaining highly indistinguishable photons [Somaschi et.al, Nature Photon. 2016].