Efficient coupling of high intensity short laser pulses into snow clusters

Abstract

Measurements of energy absorption of high intensity laser pulses in snow clusters are reported. Targets consisting of sapphire coated with snow nanoparticles were found to absorb more than 95% of the incident light compared to 50% absorption in flat sapphire targets.

Effects of front-surface target structures on properties of relativistic laser-plasma electrons

“…There is a substantial body of experimental work on the effect of surface roughness of targets on laser-plasma coupling, including the laser absorption and the production efficiency and energy spectrum of the generated xrays or ions [14][15][16][17][18][19][20][21]. Various simulation works attribute the observed improvement to a surface area increase and the local field enhancement introduced by the roughness [22][23][24][25].…”

Proton Acceleration by Ultrashort Intense Laser Interaction with Microstructured Snow Targets

“…These targets were engineered by depositing snow on sapphire substrates. It was shown that pre-formed plasma formed by a prepulse may be beneficial to the acceleration process [17,18]. Our experimental results [16] show that the energy of the accelerated protons scales with the power of the laser according to ~ / , like other schemes [19] (see Figure 1).…”

Efficient ion generation in laser-foil interaction

“…The subwavelength-multiholes transpiercing the planar target enhance the laser-proton energy conversion efficiency [21][22][23]. The subwavelength microstructured targets [21][22][23][24][25] are propitious to enhance the laser energy absorption. In this paper a e-mail: kwt@cc.utsunomiya-u.ac.jp This is an Open Access article distributed under the terms of the Creative Commons Attribution License 2.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.…”