Speaker
Description
Nanostructured targets allow better performance of laser-driven experiments due to deep penetration of laser radiation and uniform heating of the target. For correct implementation of experimental, tasks it is important to preserve the target form during all exposition time. However, laser prepulse influence is inevitable and the energy amount transferred during the prepulse can be considerable. In this work, we studied the influence of laser contrast on the generation of the overcritical layer in front of the nanostructured target and nanowires implosion. We considered aluminum nanowire arrays with different fulfillment factors supposed to be a prepulse with form reproduced from the real experiments implemented at ELI-NP. We implemented numerical simulations using radiation-hydrodynamic FLASH code. We observed the implosion for 250ps laser prepulse for 1PW laser. As well, overcritical density regions are generated in front of the nanowires. A continuous overcritical density layer appears only for 10 PW laser after 250 ps prepulse. Moreover, we estimated the implosion speed, as the speed of the overcritical density region. The implosion speed is higher than the speed of sound in the nanowires, but lower than the sound speed in plasma.
