Plasma waveguide formation using axicon ignitor-heater scheme in high-density gas clustered target for amplification of the soft x-ray laser radiation

To boost energy output of the soft x-ray laser the waveguiding technique can be used. Hence we investigated plasma waveguide properties in the high-density gas clustered target. The investigated density range was from 6.5MPa up to 15MPa of the backing pressure of 5mm resp. 10mm x 0.4mm gas jet. The waveguide is formatted by thermal expansion. For the ignitor prepulse, was used low energy femtosecond beam, and for the heater prepulse, was used a picosecond beam. The spatial, the spectral and the temporal characteristics were experimentally measured for both jets with fundamental and second harmonic wavelengths and different ignitorheater configurations.