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arXiv · 1701.09129

Experimentally Exploring the Interatomic Potential in a Ferroelectric Crystal via Optimal Ultrafast Lattice Control

Blake S. Dastrup·Jacob R. Hall·Jeremy A. Johnson
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Abstract

We present a direct comparison between resonant terahertz (THz) and nonresonant impulsive stimulated Raman scattering (ISRS) excitation of phonon-polaritons in ferroelectric lithium niobate. THz excitation offers advantages of selectively driving only the forward propagating phonon-polariton mode to exceedingly high amplitudes, without complications due to nonlinear processes at the high 800 nm pump fluences used in Raman excitation. At peak-to-peak THz electric field strengths exceeding 1 MV/cm, the ferroelectric lattice is driven into the anharmonic regime, allowing experimental determination of the shape of the potential energy surface.

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Blake S. Dastrup, Jacob R. Hall, Jeremy A. Johnson. 2017-01-31. Experimentally Exploring the Interatomic Potential in a Ferroelectric Crystal via Optimal Ultrafast Lattice Control. https://arxiv.org/abs/1701.09129

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