The LICPA-driven collider—a novel efficient tool for the production of ultra-high pressures in condensed media

Abstract

A: Generation of strong shock waves for the production of Mbar or Gbar pressures is a topic of high relevance for contemporary research in various domains, including inertial confinement fusion, laboratory astrophysics, planetology and material science. The pressures in the multi-Mbar range can be produced by the shocks generated using chemical explosions, light-gas guns, Z-pinch machines or lasers. Higher pressures, in the sub-Gbar or Gbar range are attainable only with nuclear explosions or laser-based methods. Unfortunately, due to the low efficiency of energy conversion from a laser to the shock (below a few percent), multi-kJ, multi-beam lasers are needed to produce such pressures with these methods. Here, we propose and investigate a novel scheme for generating high-pressure shocks which is much more efficient than the laser-based schemes known so far. In the proposed scheme, the shock is generated in a dense target by the impact of a fast projectile driven by the laser-induced cavity pressure acceleration (LICPA) mechanism. Using two-dimensional hydrodynamic simulations and the measurements performed at the kilojoule PALS laser facility it is shown that in the LICPA-driven collider the laser-to-shock energy conversion efficiency can reach a very high value ∼ 15-20 % and, as a result, the shock pressure ∼ 0.5-1 Gbar can be produced using lasers of energy 0.5 kJ. On the other hand, the pressures in the multi-Mbar range could be produced in this collider with low-energy (∼ 10 J) lasers available on the market. It would open up the possibility of conducting research in high energy-density science also in small, university-class laboratories. K: Plasma generation (laser-produced, RF, x ray-produced); Plasma diagnostics -interferometry, spectroscopy and imaging 1Corresponding author.

Efficient acceleration of a dense plasma projectile to hyper velocities in the laser-induced cavity pressure acceleration scheme

“…That is why to determine this factor we used numerical simulations employing the two-dimensional (2D) hydrodynamic PALE code [26,27]. Based on the simulations performed for the parameters of the CH/Au target, the accelerator and the laser pulse such as those in the experiment (for more details see [28]) we found that for E L = 200 J the factor  ≈ 1.36 ± 0.02. These simulations also indicated that the moment the projectile is leaving the accelerator channel about 90 % of the mass and kinetic energy of the projectile is stored inside a small region of the size Δz p < 0.1 mm (Fig.…”

“…It has been shown that in the accelerator with a 200-J laser driver a 4-g gold plasma projectile can be accelerated to the velocity of 140 km/s with the energetic acceleration efficiency of 15 -19 % which is at least by a factor 5 -10 higher than those achieved in the ablative acceleration schemes and is the highest among the ones measured so far for any projectiles accelerated to the velocities ≥ 100 km/s. Such high acceleration efficiency coupled with the high density of the projectile driven by LICPA makes it possible to produce high-pressure shocks by the projectile impact much more efficiently than with the methods used so far [28]. As a result, to create high-energydensity matter states, e.g.…”

Design of plasma shutters for improved heavy ion acceleration by ultra-intense laser pulses

“…The simulations involve a heat conductivity numerical model [70] and heat flux limiter, simple critical-density and wave-based laser absorption models [71], Spitzer-Harm heat conductivity model [72] and realistic Quotidian equation of State [73]. This code is commonly used for interpretation of experiments involving nanosecond pulses [74][75][76]. The simulation uses a 2D computational r-z mesh containing 100 × 100 cells including a 40 nm thick and 25 µm long foil of solid aluminum at room temperature.…”