Rapid heating of solid density material by a petawatt laser

Abstract

Time-resolved x-ray spectra from solid targets irradiated by the VULCAN Petawatt laser focused to 1020Wcm−2 show that material at solid density is heated to temperatures above 500 eV to a depth of about 15 μm and for a duration of more than 30 ps. Modeling with the implicit hybrid plasma code LSP shows that the heating is sensitive to the laser prepulse through resistive inhibition of the laser accelerated electrons in the blow off layer.

Precision X-ray spectroscopy of intense laser-plasma interactions

“…This suggests that the temperature of the isotropic component is low and possibly around 200 eV. This is broadly in agreement with previous measurement and simulation [26,27]. The excitation of the Ly-a transition leading to a polarisation of P w 0.22 indicates the presence of an anisotropic or beam-like electron population with temperatures higher than that of the isotropic component of the return current and orders-ofmagnitude less than the MeV fast electron temperature.…”

Modeling target bulk heating resulting from ultra-intense short pulse laser irradiation of solid density targets

“…[18][19][20] To do so, the density n h and temperature T h of the hot electron source, as well as the bulk electron temperature T c (and therefore the ionization degree of the target ions), 23 are adjusted so that the simulated phase maps best fit the measured phase maps. Note that the thus inferred hot and bulk electron parameters correspond to effective values, i.e., those determining the observed rear-side plasma dynamics.…”

Feasibility study of measuring the temperature and pressure of warm dense matter.

“…At intensities of the order of 10 19 W/cm 2 , the laser drives a high current through the sample which heats the target (Figure 1) through Ohmic/resistive losses [4][5][6][7]. Laser-to-electron energy conversion efficiency is ∼10 -1 and the resulting heat deposition can be up to keV at target center down to 100eV at the target edges.…”