Data for: "Multiexcitonic Lasing in Thin-Shell Colloidal Quantum Dot Supraparticles"

Self-assembled supraparticles (SPs) of semiconductor nanocrystals function as solution-processable microlasers, where the optical gain of nanocrystals couples to whispering gallery mode resonances of microspherical cavities. Multicolour lasing from SPs is demonstrated by exploiting multiexcitonic emission of standard-sized (5.5–6.5 nm) CdSxSe1-x/ZnS colloidal quantum dots (QDs). Compound SPs were formed by combining QDs with bandgaps lower than the optical pump (λ = 625 nm) with QDs of similar (λ = 540 nm) or higher bandgap (λ = 490 nm) relative to the pump (λ = 532 nm). At low pump fluence, lasing occurs in the red region (2.00–2.04 eV) from 1S state recombination. With increasing fluence, a transition to yellow lasing (2.14–2.18 eV) is induced from higher-energy 1P states. This red-to-yellow shift enables fluence-controlled tuning of lasing output in SPs of standard-sized QDs, and the adopted strategy paves the way for compound-engineered multicolour microlasers.