PIC SIMULATION EVIDENCE FOR ULTRARELATIVISTIC ELECTRON BUNCHES PRODUCED BY NON-LINEAR LASER WAKEFIELD ACCELERATION

External injection of electron bunches into laser-driven plasma waves so far has not resulted in ‘controlled’ acceleration, i.e. production of bunches with well-defined energy spread. Recent simulations, however, predict that narrow distributions can be achieved, provided the conditions for properly trapping the injected electrons are met. Under these conditions, injected bunch lengths of one to several plasma wavelengths are acceptable. This paper first describes current efforts to demonstrate this experimentally, using state-of-the-art radio frequency technology. The expected charge accelerated, however, is still low for most applications. In the second part, the paper addresses a number of novel concepts for significant enhancement of photo-injector brightness. Simulations predict that, once these concepts are realized, external injection into a wakefield accelerator will lead to accelerated bunch specs comparable to those of recent ‘laser-into-gasjet’ experiments, without the present irreproducibility of charge and final energy of the latter.

Download Full-text

Direct Imaging with Hundreds of MeV Electron Bunches from Laser Wakefield Acceleration

physica status solidi (a) ◽

10.1002/pssa.202000371 ◽

2020 ◽

Vol 218 (1) ◽

pp. 2000371

Author(s):

Chaofan Xiao ◽

Zhiyi Xu ◽

Haiyang Lu ◽

Jiaxin Liu ◽

Chengzhi Xie ◽

...

Keyword(s):

Laser Wakefield Acceleration ◽

Direct Imaging ◽

Electron Bunches ◽

Wakefield Acceleration ◽

Laser Wakefield

Download Full-text

Generation of high-quality electron beams by ionization injection in a single acceleration stage

High Power Laser Science and Engineering ◽

10.1017/hpl.2016.25 ◽

2016 ◽

Vol 4 ◽

Cited By ~ 8

Author(s):

Nasr A.M. Hafz ◽

Song Li ◽

Guangyu Li ◽

Mohammad Mirzaie ◽

Ming Zeng ◽

...

Keyword(s):

Electron Beams ◽

Laser Pulses ◽

Electron Trapping ◽

Laser Wakefield Acceleration ◽

Plasma Parameters ◽

Electron Bunches ◽

Wakefield Acceleration ◽

Low Concentrations ◽

Laser Wakefield ◽

Complex Target

Ionization-induced electron injection in laser wakefield accelerators, which was recently proposed to lower the laser intensity threshold for electron trapping into the wake wave, has the drawback of generating electron beams with large and continuous energy spreads, severely limiting their future applications. Complex target designs based on separating the electron trapping and acceleration stages were proposed as the only way for getting small energy-spread electron beams. Here, based on the self-truncated ionization-injection concept which requires the use of unmatched laser–plasma parameters and by using tens of TW laser pulses focused onto a gas jet of helium mixed with low concentrations of nitrogen, we demonstrate single-stage laser wakefield acceleration of multi-hundred MeV electron bunches with energy spreads of a few percent. The experimental results are verified by PIC simulations.

Download Full-text