Multiphoton nonclassical light from clusters of single-photon emitters

We study nonclassical features of multiphoton light emitted by clusters of single-photon emitters. As signatures of nonclassicality, we use violation of inequalities for normalized correlation functions of different orders or the probabilities of multiphoton detection. In particular, for clusters of 2-14 colloidal CdSe/CdS dot-in-rods we observe antibunching and nonclassicality of up to the fourth-order. Surprisingly, violation of certain classical inequalities gets even more pronounced for larger clusters.