TITLE:
Influence of Photon Pump Fluence on Charge Carriers in FAPbI3 and Manganite Perovskites
AUTHORS:
Nam Joong Jeon, Jangwon Seo, Sanghee Nah, Jung-Keun Lee
KEYWORDS:
FAPbI3, Perovskite Manganites, Transient Absorption
JOURNAL NAME:
Advances in Chemical Engineering and Science,
Vol.12 No.1,
January
21,
2022
ABSTRACT: FAPbI3 and FA(Mn:Pb)I3 perovskite films were
prepared and evaluated through steady and transient absorption
spectroscopy. According to the analysis using Elliot’s model, there were no
considerable differences except for the absorption intensity between FAPbI3 and FA(Mn:Pb)I3 perovskite films: the value of the optical gap (Eg)
and the position of exciton resonance (E0) were the same. The femtosecond transient absorption showed
biexponential relaxation properties of the charge carriers, suggesting
that biexcitons are more easily generated in FA(Mn:Pb)I3 than FAPbI3 perovskite. The generation of biexcitons in FA(Mn:Pb)I3 was also
confirmed by the photon pump fluence dependence. Moreover, we were able to
estimate the average number of absorbed photons directly from
the photon pump power dependence without needing any further experimental
measurements such as photoluminescence. Our findings may offer a new way of
understanding photoinduced carrier dynamics in perovskite manganites.