Dynamics of coherent phonons in CsPbCl₃ nanocrystals studied by femtosecond laser spectroscopy

Abstract

We report on the generation of coherent optical phonons in CsPbCl 3 nanocrystals in CsCl by femtosecond laser-pulse illumination. The oscillations of four confined phonon modes were identified and their properties (amplitude, frequency, and phase) in dependence on the excitation laser pulse wavelength were studied. The results are interpreted in terms of spectral dependence of the phonon generation mechanism.