"Measurement of transient atomic displacements in thin films with picosecond and femtometer resolution"

M. Kozina: T. Hu, J. S. Wittenberg, E. Szilagyi, M. Trigo, T. A. Miller, C. Uher, A. Damodaran, L. Martin, A. Mehta, J. Corbett, J. Safranek, D. A. Reis and A. M. Lindenberg ; Struc. Dyn., 05/06/2014.

Additional Authors: T. Hu, J. S. Wittenberg, E. Szilagyi, M. Trigo, T. A. Miller, C. Uher, A. Damodaran, L. Martin, A. Mehta, J. Corbett, J. Safranek, D. A. Reis and A. M. Lindenberg

Abstract:

We report measurements of the transient structural response of weakly photo-excited thin films of BiFeO, Pb(Zr,Ti)O, and Bi and time-scales for interfacial thermal transport. Utilizing picosecond x-ray diffraction at a 1.28 MHz repetition rate with time resolution extending down to 15 ps, transient changes in the diffraction angle are recorded. These changes are associated with photo-induced lattice strains within nanolayer thin films, resolved at the part-per-million level, corresponding to a shift in the scattering angle three orders of magnitude smaller than the rocking curve width and changes in the interlayer lattice spacing of fractions of a femtometer. The combination of high brightness, repetition rate, and stability of the synchrotron, in conjunction with high time resolution, represents a novel means to probe atomic-scale, near-equilibrium dynamics.