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arXiv · 1703.09818

Ultrafast x-ray diffraction probe of terahertz field-driven soft mode dynamics

M. Kozina·T. van Driel·M. Chollet·T. Sato·J. M. Glownia·S. Wandel·M. Radovic·U. Staub·M. C. Hoffmann
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Abstract

We use ultrafast x-ray pulses to characterize the lattice response of SrTiO3 when driven by strong terahertz (THz) fields. We observe transient changes in the diffraction intensity with a delayed onset with respect to the driving field. Fourier analysis reveals two frequency components corresponding to the two lowest energy zone-center optical modes in SrTiO3. The lower frequency mode exhibits clear softening as the temperature is decreased while the higher frequency mode shows slight temperature dependence.

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M. Kozina, T. van Driel, M. Chollet, T. Sato, J. M. Glownia, S. Wandel, M. Radovic, U. Staub, M. C. Hoffmann. 2017-03-28. Ultrafast x-ray diffraction probe of terahertz field-driven soft mode dynamics. https://arxiv.org/abs/1703.09818

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