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  • Temperature‐Dependent Recombination Dynamics of Photocarriers in CsPbBr 3 Microcrystals Revealed by Ultrafast Terahertz Spectroscopy
Title: Temperature‐Dependent Recombination Dynamics of Photocarriers in CsPbBr 3 Microcrystals Revealed by Ultrafast Terahertz Spectroscopy
Abstract The ultrafast dynamics of photoexcited charge carriers are studied in micron‐scale crystals composed of the inorganic perovskite CsPbBr3with time‐resolved terahertz spectroscopy. Exciting with photon energy close to the band edge, it is found that a fast (<10 ps) decay emerges in the terahertz photoconductivity with increasing pump fluence and decreasing temperature, dominating the dynamics at 4 K. The fluence‐dependent dynamics can be globally fit by a nonlinear recombination model, which reveals that the influence of different nonlinear recombination mechanisms in the studied pump fluence range depends on temperature. Whereas the Auger scattering rate decreases with decreasing temperature from 77 to 4 K, the radiative recombination rate increases by three orders of magnitude. Spectroscopically, the terahertz photoconductivity resembles a Drude response at all delays, yet an additional Lorentz component due to an above‐bandwidth resonance is needed to fully reproduce the data.  more » « less
Award ID(s):
2316827
PAR ID:
10608949
Author(s) / Creator(s):
; ; ; ; ; ; ;
Publisher / Repository:
Advanced Optical Materials
Date Published:
Journal Name:
Advanced Optical Materials
Volume:
12
Issue:
30
ISSN:
2195-1071
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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