Abstract

One of the chief attractive properties of the relativistic and ponderomotive self-channeling of ultra-intense laser pulses in underdense plasmas [1,2] is the ability to control the stability of channel formation even when the initial peak power of the pulse P₀ substantially exceeds the critical power P_cr and the initial radius of the beam r₀ is much larger than the channel radius r_ch – the situation that typically leads to unstable self-channeling in initially uniform plasmas [3]. The essence of the stability control is the multi-stage channel formation with an appropriately increasing electron density gradient at the initial stage of the self-channeling [4]. This paper reports the results of recent experimental and numerical studies of the stability, efficiency, and robustness of the relativistic self-channeling of multi-TW UV pulses in underdense plasmas. The key findings are (1) the substantially increased power efficiency of the multi-stage relativistic self-channeling compared with the channel formation in initially uniform plasmas and (2) an exceptional level of stability and robustness of the relativistic channel formation.

© 2013 IEEE