Faraday-rotation self-interference method for electron beam duration measurement in the laser wakefield accelerator

Liu, Jiaqi and Li, Wentao and Liu, Jiansheng and Qin, Zhiyong and Wang, Wentao and Qi, Rong and Zhang, Zhijun and Yu, Changhai and Fang, Ming and Wang, Cheng and Li, Ruxin (2018) Faraday-rotation self-interference method for electron beam duration measurement in the laser wakefield accelerator. Chinese Optics Letters, 16 (7). ISSN 1671-7694

[thumbnail of Liu-etal-2018-Faraday-rotation-self-interference-method-for-electron-beam-duration-measurement]
Preview
Text. Filename: Liu_etal_2018_Faraday_rotation_self_interference_method_for_electron_beam_duration_measurement.pdf
Final Published Version

Download (1MB)| Preview

Abstract

Real-time single-shot measurement of the femtosecond electron beam duration in laser wakefield accelerators is discussed for both experimental design and theoretical analysis that combines polarimetry and interferometry. The probe pulse polarization is rotated by the azimuthal magnetic field of the electron beam and then introduced into a Michelson-type interferometer for self-interference. The electron beam duration is obtained from the region size of the interference fringes, which is independent of the pulse width of the probe laser. Using a larger magnification system or incident angle, the measurement resolution can be less than 1 fs.