title: Demonstration of self-truncated ionization injection for GeV electron beams.
abstract: Ionization-induced injection mechanism was introduced in 2010 to reduce the laser intensity threshold for controllable electron trapping in laser wakefield accelerators (LWFA). However, usually it generates electron beams with continuous energy spectra. Subsequently, a dual-stage target separating the injection and acceleration processes was regarded as essential to achieve narrow energy-spread electron beams by ionization injection. Recently, we numerically proposed a self-truncation scenario of the ionization injection process based upon overshooting of the laser-focusing in plasma which can reduce the electron injection length down to a few hundred micrometers, leading to accelerated beams with extremely low energy-spread in a single-stage. Here, using 100 TW-class laser pulses we report experimental observations of this injection scenario in centimeter-long plasma leading to the generation of narrow energy-spread GeV electron beams, demonstrating its robustness and scalability. Compared with the self-injection and dual-stage schemes, the self-truncated ionization injection generates higher-quality electron beams at lower intensities and densities, and is therefore promising for practical applications.
authors.affiliation: Key Laboratory for Laser Plasmas (MOE) and Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China.|IFSA Collaborative Innovation Center, Shanghai Jiao Tong University, Shanghai 200240, China.
authors.forename: M
authors.initials: M
authors.lastname: Mirzaie
authors.affiliation: Key Laboratory for Laser Plasmas (MOE) and Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China.|IFSA Collaborative Innovation Center, Shanghai Jiao Tong University, Shanghai 200240, China.
authors.forename: S
authors.initials: S
authors.lastname: Li
authors.affiliation: Key Laboratory for Laser Plasmas (MOE) and Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China.|IFSA Collaborative Innovation Center, Shanghai Jiao Tong University, Shanghai 200240, China.
authors.forename: M
authors.initials: M
authors.lastname: Zeng
authors.affiliation: Key Laboratory for Laser Plasmas (MOE) and Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China.|IFSA Collaborative Innovation Center, Shanghai Jiao Tong University, Shanghai 200240, China.
authors.forename: N A M
authors.initials: NA
authors.lastname: Hafz
authors.affiliation: Key Laboratory for Laser Plasmas (MOE) and Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China.|IFSA Collaborative Innovation Center, Shanghai Jiao Tong University, Shanghai 200240, China.
authors.forename: M
authors.initials: M
authors.lastname: Chen
authors.affiliation: Key Laboratory for Laser Plasmas (MOE) and Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China.|IFSA Collaborative Innovation Center, Shanghai Jiao Tong University, Shanghai 200240, China.
authors.forename: G Y
authors.initials: GY
authors.lastname: Li
authors.affiliation: College of Science, National University of Defense Technology, Changsha 410073, China.
authors.forename: Q J
authors.initials: QJ
authors.lastname: Zhu
authors.affiliation: College of Science, National University of Defense Technology, Changsha 410073, China.
authors.forename: H
authors.initials: H
authors.lastname: Liao
authors.affiliation: Key Laboratory for Laser Plasmas (MOE) and Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China.|IFSA Collaborative Innovation Center, Shanghai Jiao Tong University, Shanghai 200240, China.
authors.forename: T
authors.initials: T
authors.lastname: Sokollik
authors.affiliation: Key Laboratory for Laser Plasmas (MOE) and Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China.|IFSA Collaborative Innovation Center, Shanghai Jiao Tong University, Shanghai 200240, China.
authors.forename: F
authors.initials: F
authors.lastname: Liu
authors.affiliation: IFSA Collaborative Innovation Center, Shanghai Jiao Tong University, Shanghai 200240, China.|College of Science, National University of Defense Technology, Changsha 410073, China.
authors.forename: Y Y
authors.initials: YY
authors.lastname: Ma
authors.affiliation: IFSA Collaborative Innovation Center, Shanghai Jiao Tong University, Shanghai 200240, China.|Beijing National Laboratory of Condensed Matter Physics, Institute of Physics, CAS, Beijing 100190, China.
authors.forename: L M
authors.initials: LM
authors.lastname: Chen
authors.affiliation: Key Laboratory for Laser Plasmas (MOE) and Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China.|IFSA Collaborative Innovation Center, Shanghai Jiao Tong University, Shanghai 200240, China.|SUPA, Department of Physics, University of Strathclyde, Glasgow G4 0NG, UK.
authors.forename: Z M
authors.initials: ZM
authors.lastname: Sheng
authors.affiliation: Key Laboratory for Laser Plasmas (MOE) and Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China.|IFSA Collaborative Innovation Center, Shanghai Jiao Tong University, Shanghai 200240, China.
authors.forename: J
authors.initials: J
authors.lastname: Zhang