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arXiv · 0904.0795

Implicit spatial averaging in inversion of inelastic x-ray scattering data

P. Abbamonte·J. P. Reed·Y. I. Joe·Yu Gan·D. Casa
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Abstract

Inelastic x-ray scattering (IXS) now a widely used technique for studying the dynamics of electrons in condensed matter. We previously posed a solution to the phase problem for IXS [P. Abbamonte, et. al., Phys. Rev. Lett. {\bf 92}, 237401 (2004)], that allows explicit reconstruction of the density propagator of a system. The propagator represents, physically, the response of the system to an idealized, point perturbation, so provides direct, real-time images of electron motion with attosecond time resolution and $\AA$-scale spatial resolution. Here we show that the images generated by our procedure, as it was originally posed, are spatial averages over all source locations. Within an idealized, atomic-like model, we show that in most cases a simple relationship to the complete, un-averaged response can still be determined. We illustrate this concept for recent IXS measurements of single crystal graphite.

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P. Abbamonte, J. P. Reed, Y. I. Joe, Yu Gan, D. Casa. 2009-04-06. Implicit spatial averaging in inversion of inelastic x-ray scattering data. https://doi.org/10.1103/physrevb.80.054302

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