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تسجيل مستخدم جديدUltrafast Imaging and the Phase Problem for Inelastic X-Ray Scattering
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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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