LIGHT PIPE FOR HIGH-INTENSITY LASER-PULSES

Optical guiding of intense laser pulses over a distance, of more than 20 Rayleigh lengths in a plasma is demonstrated using a two-pulse technique. The first pulse prepares a shock-driven, axially extended radial electron density profile which guides a second pulse, injected after an optimum delay which increases with mass of the plasma ion's. In the intensity range considered here (10(13)-10(14) W/cm2), the channel is observed to support mode structure reminiscent of an optical waveguide.