The prospect of using the quantum nature of light for secure communication keeps spurring the search and investigation of suitable sources of entangled-photons. Semiconductor quantum dots are arguably the most attractive. They can generate indistinguishable entangled-photons deterministically, and are compatible with current photonic-integration technologies, a set of properties not shared by any other entanglement resource. However, as no two quantum dots are identical, they emit entangled-photons with random energies. This hinders their exploitation in communication protocols requiring entangled-states with well-defined energies. Here, we introduce scalable quantum-dot-based sources of polarization-entangled-photons whose energy can be controlled via dynamic strain-engineering without degrading the degree of entanglement of the source. As a test-bench, we interface quantum dots with clouds of atomic vapours, and we demonstrate slow-entangled-photons from a single quantum emitter. These results pave the way towards the implementation of hybrid quantum networks where entanglement is distributed among distant parties using scalable optoelectronic devices.
@article{arxiv.1507.06612,
title = {Scalable Sources of Entangled Photons with Wavelength on Demand},
author = {Rinaldo Trotta and Javier Martin-Sanchez and Johannes S. Wildmann and Giovanni Piredda and Marcus Reindl and Christian Schimpf and Eugenio Zallo and Oliver G. Schmidt and Sandra Stroj and Johannes Edlinger and Armando Rastelli},
journal= {arXiv preprint arXiv:1507.06612},
year = {2015}
}