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arXiv · 1211.1464

X-ray amplification from a Raman Free Electron Laser

Igor Andriyash·Emmanuel D'Humieres·Vladimir Tikhonchuk·Philippe Balcou
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Abstract

We demonstrate that a mm-scale free electron laser can operate in the X-ray range, in the interaction between a moderately relativistic electron bunch, and a transverse high intensity optical lattice. The corrugated light-induced ponderomotive potential acts simultaneously as a guide and as a low-frequency wiggler, triggering stimulated Raman scattering. The gain law in the small signal regime is derived in a fluid approach, and confirmed from Particle-In-Cell simulations. We describe the nature of bunching, and discuss the saturation properties. The resulting all-optical Raman X-ray laser opens perspectives for ultra-compact coherent light sources up to the hard X-ray range.

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Igor Andriyash, Emmanuel D'Humieres, Vladimir Tikhonchuk, Philippe Balcou. 2012-11-07. X-ray amplification from a Raman Free Electron Laser. https://doi.org/10.1103/physrevlett.109.244802

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