TJ cm−3 high energy density plasma formation from intense laser-irradiated foam targets composed of disordered carbon nanowires

High energy density plasma formation from intense laser-irradiated foam targets composed of disordered carbon nanowires is investigated using three-dimensional particle-in-cell simulations. It is shown that due to the unprecedentedly high laser energy absorption rate of the foam target, approximately three times larger as compared with simple solid targets, the plasma energy density reaches an unexplored TJ cm−3 regime at 1023 W cm−2 laser irradiation. In addition, nanowire thermal expansion caused by prepulse heating is considered. We find that after expansion, the target becomes relativistically transparent to the main pulse. The average value of particle energy density decreases slightly and its distribution tends to resemble that of solid targets. Furthermore, energy density scaling with laser intensities is given. It suggests that an even more extreme plasma state is reachable using ultraintense lasers, as the energy loss to photons caused by quantum electrodynamics effects is rather negligible.