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arXiv · 2110.08234

Terahertz Kerr effect in a methylammonium lead bromide perovskite crystal

A. A. Melnikov·V. E. Anikeeva·O. I. Semenova·S. V. Chekalin
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Abstract

We have observed short-lived optical birefringence in a CH$_3$NH$_3$PbBr$_3$ single crystal induced by a powerful nearly single-cycle terahertz pulse. Apart from the instantaneous contribution that follows the profile of the squared pump electric field, the recorded anisotropy signal contains an exponential component decaying in $\sim$ 350 fs, underdamped oscillations at the frequency of $\sim$ 0.16 THz and an intermediate picosecond relaxation process with a Gaussian tail. We associate these three non-trivial features with, respectively, Kerr effect in the inorganic lattice, terahertz-induced transient alignment of CH$_3$NH$_3^+$ cations, and their coherent rotation excited by the terahertz pulse in a Raman process.

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A. A. Melnikov, V. E. Anikeeva, O. I. Semenova, S. V. Chekalin. 2021-10-15. Terahertz Kerr effect in a methylammonium lead bromide perovskite crystal. https://doi.org/10.1103/physrevb.105.174304

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