Photoinduced Vibrations Drive Ultrafast Structural Distortion in Lead Halide Perovskite.

ABSTRACT: The success of organic-inorganic perovskites in optoelectronics is dictated by the complex interplay between various underlying microscopic phenomena. The structural dynamics of organic cations and the inorganic sublattice after photoexcitation are hypothesized to have a direct effect on the material properties, thereby affecting the overall device performance. Here, we use ultrafast heterodyne-detected two-dimensional (2D) electronic spectroscopy to reveal impulsively excited vibrational modes of methylammonium (MA) lead iodide perovskite, which drive the structural distortion after photoexcitation. Vibrational analysis of the measured data allows us to monitor the time-evolved librational motion of the MA cation along with the vibrational coherences of the inorganic sublattice. Wavelet a

SUBMITTER: Duan HG 

PROVIDER: S-EPMC7586332 | biostudies-literature | 2020 Sep

REPOSITORIES: biostudies-literature