A semiconductor deterministic bright source of entangled photon pairs

In this work, we show that this drawback can be overcome by coupling an optical cavity in the form of a ´photonic molecule´ to a single QD. Two coupled identical pillars are etched in a semiconductor planar microcavity, using an optical lithography method that ensures a deterministic coupling to the optical transitions of a pre-selected quantum dot. Acceleration of spontaneous emission ensures that most entangled photon pairs are emitted into two cavity modes, while improving the indistinguishability of the two optical recombination paths.