Artificial collimation of fast-electron beams with two laser pulses.

A scheme for artificially collimating fast-electron beams produced in high intensity (>10(19) W cm(-2)) laser-solid interactions is proposed. The scheme uses a laser pulse at the relativistic threshold (approximately 10(18) W cm(-2)) that precedes the high intensity pulse to pregenerate a collimating magnetic field. This concept is supported by analytical calculations and numerical calculations performed using a novel hybrid-Vlasov-Fokker-Planck code called LEDA. This scheme may be highly useful for fast ignition inertial confinement fusion.