Spectroscopy of CsPbBr3 quantum dots in CsBr:Pb crystals

Absorption, emission and excitation spectra of small CsPbBr3 aggregates (nanocrystals), thermally created in CsBr:Pb single crystals, have been studied at 4.2-300 K. A strong influence of crystal structure imperfections. lead concentration, crystal quenching conditions as well as annealing temperature and duration on the optical characteristics of CsPbBr3 nanocrystals has been detected and analysed. Quantum size effects have been observed for the systems studied. A clear structure of the spectral bands has been found for some samples. Polarization of the CsPbBr3 luminescence has been detected. New information has been obtained on the size, structure and shape of CsPbBr3 nanocrystals, their orientation in the CsBr:Pb crystal lattice and on their formation processes. (C) 2001 Elsevier Science B.V. All rights reserved.