title: Spectrally peaked electron beams produced via surface guiding and acceleration in femtosecond laser-solid interactions.
abstract: Highly collimated MeV electron beam guiding has been observed along the target surface following the interaction of bulk target irradiation by femtosecond laser pulses at relativistic intensities. The beam quality is shown to depend critically on the laser contrast: With a ns prepulse, the generated electron beam is well concentrated and intense, while a high laser contrast produces divergent electron beams. In the case of large preplasma scale lengths, tunable guiding and acceleration of the target surface electrons is achieved by changing the laser incident angle. By expanding the preplasma scale length to several hundred micrometers, we obtained MeV spectrum-peaked electron beams with a 100 pC per laser pulse and divergence angles of only 3°. This technique suggests a stable method of injection of elections into a variety of accelerator designs.
authors.affiliation: Beijing National Laboratory of Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: J Y
authors.initials: JY
authors.lastname: Mao
authors.forename: L M
authors.initials: LM
authors.lastname: Chen
authors.forename: X L
authors.initials: XL
authors.lastname: Ge
authors.forename: L
authors.initials: L
authors.lastname: Zhang
authors.forename: W C
authors.initials: WC
authors.lastname: Yan
authors.forename: D Z
authors.initials: DZ
authors.lastname: Li
authors.forename: G Q
authors.initials: GQ
authors.lastname: Liao
authors.forename: J L
authors.initials: JL
authors.lastname: Ma
authors.forename: K
authors.initials: K
authors.lastname: Huang
authors.forename: Y T
authors.initials: YT
authors.lastname: Li
authors.forename: X
authors.initials: X
authors.lastname: Lu
authors.forename: Q L
authors.initials: QL
authors.lastname: Dong
authors.forename: Z Y
authors.initials: ZY
authors.lastname: Wei
authors.forename: Z M
authors.initials: ZM
authors.lastname: Sheng
authors.forename: J
authors.initials: J
authors.lastname: Zhang