Abstract-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

(Submitted on 28 Mar 2017)

https://arxiv.org/abs/1703.09818

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.