Heralded generation of high-purity ultrashort single photons in programmable temporal shapes
V. Ansari, E. Roccia, M. Santandrea, M. Doostdar, C. Eigner, L. Padberg, I. Gianani, M. Sbroscia, J.M. Donohue, L. Mancino, M. Barbieri, C. Silberhorn, Optics Express (2018).