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arXiv · 1205.5915

Crystallographic refinement of collective excitations using standing wave inelastic x-ray scattering

Yu Gan·Anshul Kogar·Peter Abbamonte
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Abstract

We propose a method for realizing true, real-space imaging of charge dynamics in a periodic system, with angstrom spatial resolution and attosecond time resolution. In this method, inelastic x-ray scattering (IXS) is carried out with a coherent, standing wave source, which provides the off-diagonal elements of the generalized dynamic structure factor, S(q_1,q_2,ω), allowing complete reconstruction of the inhomogeneous response function of the system, χ(x_1,x_2,t). The quantity χhas the physical meaning of a propagator for charge, so allows one to observe - in real time - the disturbance in the electron density created by a point source placed at a specified location, x_1 (on an atom vs. between atoms, for example). This method may be thought of as a generalization of x-ray crystallography that allows refinement of the excited states of a periodic system, rather than just its ground state.

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Yu Gan, Anshul Kogar, Peter Abbamonte. 2012-05-26. Crystallographic refinement of collective excitations using standing wave inelastic x-ray scattering. https://doi.org/10.1016/j.chemphys.2012.06.018

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