Formation of Abundant Quantum Emitters in 2D Lead-Halide Perovskites.

Owing to the possession of naturally formed quantum wells with strong spatial and dielectric confinements, 2D lead-halide perovskites are attracting intensive research interest in the context of potential applications in classical optoelectronic devices. Here we have synthesized a 2D (PEA)2PbI4 perovskite microplate and observed at ∼3 K that it can emit single photons from the abundant ultranarrow peaks appearing in the photoluminescence spectrum. This signifies the formation of 0D quantum emitters within the otherwise homogeneous 2D energy landscape, which can be attributed to the thickness fluctuations induced by octahedral tiltings across an inorganic sheet. These findings mark the emergence of a hybrid type of quantum emitters with both 0D and 2D confinements, thus extending the fundamental and practical studies of 2D perovskites to the prospective regime of quantum information technologies.