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arXiv · 1903.06112

Laser Driven Ultra-compact Undulator for Synchrotron Radiation

Junhao Tan·Yifei Li·Baojun Zhu·Changqing Zhu·Jinguang Wang·Dazhang Li·Liming Chen
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Abstract

Laser wakefield accelerators have emerged as a promising candidate for compact synchrotron radiation and even x-ray free electron lasers. Today, to make the electrons emit electromagnetic radiation, the trajectories of laser wakefield accelerated electrons are deflected by transverse wakefield, counter-propagating laser field or external permanent magnet insertion device. Here, we propose a novel type of undulator which has a few hundred microns of period and tens of Tesla of magnetic field. The undulator consists of a bifilar capacitor-coil target which sustains strong discharge current that generates helical magnetic field around the coil axis when irradiated by a high energy laser. Coupling this undulator with state-of-the-art laser wakefield accelerators can, simultaneously, produce ultra-bright quasi-monochromatic x-rays with tunable energy ranging 5-250 keV and optimize the free electron laser parameter and gain length compared with permanent magnet based undulator. This concept may pave a path toward ultra-compact synchrotron radiation and even x-ray free electron lasers.

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Junhao Tan, Yifei Li, Baojun Zhu, Changqing Zhu, Jinguang Wang, Dazhang Li, Liming Chen. 2019-03-13. Laser Driven Ultra-compact Undulator for Synchrotron Radiation. https://arxiv.org/abs/1903.06112

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