title: Nonlinear Optics in Relativistic Plasmas and Laser Wake Field Acceleration of Electrons
abstract: When a terawatt-peak-power laser beam is focused into a gas jet, an electron plasma wave, driven by forward Raman scattering, is observed to accelerate a naturally collimated beam of electrons to relativistic energies (up to 10(9) total electrons, with an energy distribution maximizing at 2 megaelectron volts, a transverse emittance as low as 1 millimeter-milliradian, and a field gradient of up to 2 gigaelectron volts per centimeter). Electron acceleration and the appearance of high-frequency modulations in the transmitted light spectrum were both found to have sharp thresholds in laser power and plasma density. A hole in the center of the electron beam may indicate that plasma electrons were expelled radially.
authors.affiliation: Center for Ultrafast Optical Science, University of Michigan, Ann Arbor, MI 48109, USA.
authors.initials: D
authors.lastname: Umstadter
authors.initials: S
authors.lastname: Chen
authors.initials: A
authors.lastname: Maksimchuk
authors.initials: G
authors.lastname: Mourou
authors.initials: R
authors.lastname: Wagner