Room temperature single-photon emission and lasing for all-inorganic colloidal perovskite quantum dots

Abstract Recent reports regarding metal halide semiconductors of perovskite nanocrystal structures have presented us a promising future on their optoelectronic applications such as laser and light harvesting devices. In this paper, all-inorganic perovskites CsPbX3 (X=Cl, Br and I) quantum dots (QDs) with tunable fluorescence from 400 nm to 700 nm were prepared by a facile hot-injection method. Besides, random lasing with coherent feedback was observed in films of CsPbX3 QDs. Under 400 nm optical excitation at room temperature, sharp lasing peaks emission at around 427 nm, 527 nm and 539 nm with low pump thresholds intensity were achieved by halide substitution. The dynamic fluorescence from one single quantum dot also was detailed investigated. These results demonstrated that all-inorganic perovskites could be used as low-threshold and wavelength-tunable gain materials for lasing application at room-temperature.