Flayac, H.Savona, V.2017-12-042017-12-042017-12-04201710.1103/PhysRevA.96.053810https://infoscience.epfl.ch/handle/20.500.14299/142589WOS:000414395000009We review the unconventional photon blockade mechanism. This quantum effect remarkably enables a strongly sub-Poissonian light statistics, even from a system characterized by a weak single-photon nonlinearity. We revisit the past results, which can be interpreted in terms of quantum interferences or optimal squeezing, and show how recent developments on input-output field mixing can overcome the limitations of the original schemes towards passive and integrable single-photon sources. We finally present some valuable alternative schemes for which the unconventional blockade can be directly adapted.Quantum opticsOpen quantum systemsMicrocavitySingle photon sourcetext::journal::journal article::research article