Random lasing in cesium lead bromine perovskite quantum dots film

Cesium lead bromine (CsPbBr 3 ) perovskite colloidal quantum dots were prepared by hot injection method. The obtained samples were single crystal nanocubes with the average side length of 9–10 nm. The drop-casting film of the quantum dots showed obvious green stimulated emission under 400 nm femtosecond laser pumping with the full width at half maximum of about 4 nm. The laser threshold was derived to be about 471 µJ/cm 2 . The laser behavior of CsPbBr 3 quantum dots films could be attributed to random lasing modes which realized in weak scattering regimes.