Ultrafast structure and polarization dynamics in nanolayered perovskites studied by femtosecond X-ray diffraction

C v Korff Schmising, M Bargheer, M Kiel, N Zhavoronkov, M Woerner, T Elsaesser, I Vrejoiu, D Hesse, M Alexe
2007 Journal of Physics, Conference Series  
The polarization and lattice dynamics in a metal/ferroelectric/metal nanolayer system is studied by femtosecond x-ray diffraction. Two Bragg reflections provide information on the coupled dynamics of the two relevant phonon modes for ferroelectricity in perovskites, the tetragonal distortion and the ion displacement. Optical excitation of the metallic SrRuO3 (SRO) layers generates giant stress, compressing the ferroelectric PbTr0.2Ti0.8O3 (PZT) layers by up to 2%. The maximum elongation of the
more » ... elongation of the tetragonal mode is reached after 1.3 ps. With a slight delay the ferroelectric polarization P is reduced by up to 100 percent that is due to the anharmonic coupling of the two modes.
doi:10.1088/1742-6596/92/1/012177 fatcat:xyo27v5ytjgczkgdgcyakpp2we