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arXiv · 1911.10660

Polarization control of an X-ray free electron laser oscillator

Nanshun Huang·Kai Li·Haixiao Deng
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Abstract

High-intensity, fully coherent X-ray radiation with a tunable polarization over a wide spectral range is of great importance to many experiments. In this paper, we propose a tapered crossed-polarized undulator configuration for X-ray free electron laser oscillator (XFELO) to produce arbitrarily polarized X-ray pulses in hard X-ray region. A numerical example utilizing the parameters of the Shanghai High-Repetition-Rate XFEL and Extreme Light Facility (SHINE) is presented to demonstrate the generation of polarization controllable, fully coherent Hard X-ray pulses with 99.9% polarization degree and 20 KHz polarization switching rate. This scheme also holds the possibility to be used in cavity tunable XFELO.

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Nanshun Huang, Kai Li, Haixiao Deng. 2019-11-25. Polarization control of an X-ray free electron laser oscillator. https://doi.org/10.1103/physrevaccelbeams.23.030702

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