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; A M Lindenberg

doi:10.1063/1.4875347

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

Struct Dyn. 2014 May 6;1(3):034301. doi: 10.1063/1.4875347. eCollection 2014 May.

Authors

M Kozina, T Hu, J S Wittenberg¹, E Szilagyi, M Trigo, T A Miller, C Uher², A Damodaran³, L Martin³, A Mehta⁴, J Corbett⁴, J Safranek⁴, D A Reis, A M Lindenberg

Affiliations

¹ Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory , Menlo Park, California 94025, USA.
² Department of Physics, University of Michigan , Ann Arbor, Michigan 48109, USA.
³ Department of Materials Science and Engineering, University of Illinois Urbana Champaign , Urbana, Illinois 61801, USA.
⁴ Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory , Menlo Park, California 94025, USA.

Abstract

We report measurements of the transient structural response of weakly photo-excited thin films of BiFeO3, Pb(Zr,Ti)O3, 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.