"Observations of laser induced magnetization dynamics in Co/Pd multilayers with coherent x-ray scattering "

B. Wu: D. Zhu, Y. Acremann, T. A. Miller, A. M. Lindenberg, O. Hellwig, J. Stöhr, and A. Scherz; Appl. Phys. Lett., 12/22/11.

Additional Authors: D. Zhu, Y. Acremann, T. A. Miller, A. M. Lindenberg, O. Hellwig, J. Stöhr, and A. Scherz

Abstract:

We report on time-resolved coherent x-ray scattering experiments of laser induced magnetization dynamics in Co/Pd multilayers with a high repetition rate optical pump x-ray probe setup. Starting from a multi-domain ground state, the magnetization is uniformly reduced after excitation by an intense 50 fs laser pulse. Using the normalized time correlation, we study the magnetization recovery on a picosecond timescale. The dynamic scattering intensity is separated into an elastic portion at length scales above 65 nm, which retains memory of the initial domain magnetization, and a fluctuating portion at smaller length scales corresponding to domain boundary motion during recovery.