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arXiv · 0906.1276

Ultrafast Imaging and the "Phase Problem" for Inelastic X-Ray Scattering

P. Abbamonte·G. C. L. Wong·D. Cahill·J. P. Reed·R. H. Coridan·N. W. Schmidt·G. H. Lai·Y. I. Joe·D. Casa
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Abstract

We describe a new method for imaging ultrafast dynamics in condensed matter using inelastic x-ray scattering (IXS). We use the concepts of causality and irreversibility to construct a general solution to the inverse scattering problem (or "phase problem") for inelastic x-ray scattering, which enables direct imaging of dynamics of the electron density with resolutions of ~1 attosecond (10-18 sec) in time and < 1 A in space. This method is not a Fourier transform of IXS data, but a means to impose causality on the data and reconstruct the charge propagator. The method can also be applied to inelastic electron or neutron scattering. We give a general outline of phenomena that can and cannot be studied with this technique, and provide an outlook for the future.

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P. Abbamonte, G. C. L. Wong, D. Cahill, J. P. Reed, R. H. Coridan, N. W. Schmidt, G. H. Lai, Y. I. Joe, D. Casa. 2009-06-12. Ultrafast Imaging and the "Phase Problem" for Inelastic X-Ray Scattering. https://arxiv.org/abs/0906.1276

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