2024/07/22 by Chestnov, Igor, Masharin, Mikhail, Kondratyev, Valeriy +6
#FOS: Physical sciences #Materials Science (cond-mat.mtrl-sci) #Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
paper · doi:10.48550/arxiv.2407.15709
Halide perovskites, such as methylammonium lead bromide (MAPbBr3), host tightly bound three-dimensional excitons which are robust at room temperature. Excellent optical properties of MAPbBr3 allow for designing of optical single-mode waveguides and cavities in the frequency range close to the excitonic transitions. Taken together, this turns MAPbBr3 into an excellent platform for probing exciton-polariton nonlinear phenomena at room temperature. Here we investigate ultrafast non-equilibrium dynamics of polaritons under pulsed fs non-resonant excitation. We demonstrate the presence of the stimulated acoustic phonon-assisted scattering regime above threshold pump fluence, characterized by the explosive growth of emission intensity, a redshift of the emission spectral maximum, spectral narrowing, and sub-picosecond emission dynamics. Our theoretical findings are well confirmed by the results of experimental measurements.