title: Ultrashort high quality electron beam from laser wakefield accelerator using two-step plasma density profile.
abstract: In this paper, we first use the rf linac injector mechanism to generate ultrashort high quality electron beam from laser wakefield accelerator (LWFA) with two-step plasma density profile successfully. We incorporate the physics principle in the conventional rf linac injector into the LWFA by using two-step plasma density to decrease the wavelength of the wakefield in plasma. Using this mechanism, we observe a ultrashort high quality electron beam (the rms energy spread is 1.9%, and the rms bunch length is 2 fs) in the simulation. The ultrashort intense terahertz coherent radiation (200 MW, 2 fs) can be generated with the proposed laser wakefield accelerator.
authors.affiliation: Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China. zhuxw@ihep.ac.cn
authors.forename: Xiongwei
authors.initials: X
authors.lastname: Zhu