Experimental study of short high-intensity laser-pulse monomode propagation in centimeter-long capillary tubes

The monomode guided propagation of a short (500-fs) laser pulse is studied for an incident intensity in the range 1013–3×1018 W/cm2 inside a glass-walled capillary tube (length, ≈1 cm; inner radius, 15 µm). The measured transmission is constant over a large range of incident intensities (1013–1016 W/cm2) and corresponds, except for a coupling constant, to the value predicted by an analytical model for monomode guiding. For incident intensities larger than 1017 W/cm2, a drop in transmission is observed, which is attributed to plasma creation at the entrance plane of the capillary tube.