Fig. 3: GOS at the bandgap (1S) transition in 17-nm CsPbBr3 QDs enabled by strong electronic correlations at cryogenic temperature.
From: Single-photon superabsorption in CsPbBr3 perovskite quantum dots
a, Experimental absorption spectrum at 15 K (line) and 300 K (shaded area); cooling to 15 K greatly enhances the 1S absorption strength, weakly enhances the 1P transition and negligibly affects the higher-energy transitions. b,c, Theoretical one-photon transition strength \({\mathcal{F}}\) for the lowest-energy states excluding (b) and including (c) correlations, as defined in Supplementary Equation (15); the energy scale (E – E1S) is referenced to the bandgap E1S. d, Ratio A1S/A1P of the absorbance at the 1S and 1P state; the experimental ratio at 15 K (right bar) is quantitatively reproduced by the CI-EMA-based theory when accounting for electron–hole pair-state correlations (middle bar) but not when neglecting it (left bar). The dashed horizontal line indicates a ratio of 1/3 that would be anticipated solely based on the degeneracy of the 1S and 1P transitions.
