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arXiv · 1504.04544

Creation of X-Ray Transparency of Matter by Stimulated Elastic Forward Scattering

Joachim Stöhr·Andreas Scherz
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Abstract

X-ray absorption by matter has long been described by the famous Beer-Lambert law. Here we show how this fundamental law needs to be modified for high-intensity coherent x-ray pulses, now available at x-ray free electron lasers, due to the onset of stimulated elastic forward scattering. We present an analytical expression for the modified polarization-dependent Beer-Lambert law for the case of resonant core-to-valence electronic transitions and incident transform limited x-ray pulses. Upon transmission through a solid, the absorption and dichroic contrasts are found to vanish with increasing x-ray intensity, with the stimulation threshold lowered by orders of magnitude through a super-radiative coherent effect. Our results have broad implications for the study of matter with x-ray lasers.

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Joachim Stöhr, Andreas Scherz. 2015-04-17. Creation of X-Ray Transparency of Matter by Stimulated Elastic Forward Scattering. https://doi.org/10.1103/physrevlett.115.107402

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