Fig. 3. Energy transfer dynamics process in control and CsI-rich Cs₃CeI₆ film.

The TAS of the Cs₃CeI₆ control sample ranges from 320 nm to 580 nm (a) and from 550 nm to 980 nm (b). (PB for photo-bleach, PIA for photo-induced absorption, CFE for Ce Frenkel exciton, and STE for self-trapped exciton). c The PIA signal in the Cs₃CeI₆ control sample at 508 (red line) and 880 nm (blue line). The TAS of the Cs₃CeI₆ Cs-rich sample ranges from 320 nm to 580 nm (d) and from 550 nm to 980 nm (e). f Dynamics processes of CFE in control (red line) and CsI-rich sample (blue line). The pump light is a 250 nm laser with the power of 70 μW when probe light ranges from 320 nm to 580 nm and 290 μW from 550 nm to 980 nm.