Abstract

New results are presented from the first experimental demonstration of the channeling of intense laser pulses over distances much greater than a Rayleigh length¹. In this scheme, two laser pulses are used: The first pulse creates a column of hot plasma that forms a channel behind a radially expanding shock wave, and the second pulse is injected into the channel after an appropriate delay. Single-mode and multi-mode propagation of the channeled beam is observed, with the mode structure depending on the two-pulse delay, gas density, and input beam coupling. Pulses have been channeled for distances as long as 70 Rayleigh lengths at intensities of at least 10¹⁴ W/cm². As much as 75% of the energy in the focal spot of the injection lens is coupled into the guide.

© 1994 Optical Society of America