Laser-Generated Proton Beams for High-Precision Ultra-Fast Crystal Synthesis

Abstract

We present a method for the synthesis of micro-crystals and micro-structured surfaces using laser-accelerated protons. In this method, a solid surface material having a low melting temperature is irradiated with very-short laser-generated protons, provoking in the ablation process thermodynamic conditions that are between the boiling and the critical point. The intense and very quick proton energy deposition (in the ns range) induces an explosive boiling and produces microcrystals that nucleate in a plasma plume composed by ions and atoms detached from the laser-irradiated surface. The synthesized particles in the plasma plume are then deposited onto a cold neighboring, non-irradiated, solid secondary surface. We experimentally verify the synthesizing methods by depositing low-melting-material microcrystals - such as gold - onto nearby silver surfaces and modeling the proton/matter interaction via a Monte Carlo code, confirming that we are in the above described thermodynamic conditions. Morphological and crystallinity measurements indicate the formation of gold octahedral crystals with dimensions around 1.2 μm, uniformly distributed onto a silver surface with dimensions in the tens of mm2. This laser-accelerated particle based synthesis method paves the way for the development of new material synthesis using ultrashort laser-accelerated particle beams.

Enhanced laser-driven hadron sources with nanostructured double-layer targets

“…feasibility of laser-driven ion beam analysis for non-destructive materials characterization. Laser-driven ion sources have been considered to test electronic components in a harsh radiation environment [18], for thermal stress testing [19], to study ultra-fast dynamics in irradiated materials [20,21], and for materials synthesis [22,23]. Ultrashort pulsed neutron sources driven by laser-accelerated ions [24-32] have been investigated for applications such as fast neutron spectroscopy [33] and radiography [34].What make these applications particularly attractive are the requirements for the ion source.…”

Enhanced laser-driven proton acceleration using ultrasmall nanoparticles

“…Laser-driven proton acceleration, as obtained by the interaction of a high-intensity laser with a target, is a growing field of interest, in particular, for the different potential applications that are consolidating or emerging. These applications include their use in ultrafast radiography [1], novel fusion schemes [2], high-energy density matter [3], laboratory astrophysics [4], medical applications [5][6][7], novel neutron sources [8], cultural heritage [9,10], using them as injectors for larger accelerators [11,12], and material science [13][14][15][16]. Many of these applications build on the routine production of protons, where one of the main challenges is to optimize the proton energy and yield given specific laser parameters.…”

Laser-accelerated particle beams for stress testing of materials

“…Today, routinely obtained laser-generated particles, in particular protons, exhibit about 10 13 particles per shot, have a ps long duration at the source, have an energy in the tens of MeV range 1 and very good laminarity 2 . While strong effort is put to materialize different applications, such as in astrophysics 3 , 4 , bright ultra-short neutron sources 5 , 6 , medicine 7 , or injectors for large-scale accelerators 8 , 9 , material science applications are still in a very embryonic state with some interesting pioneering works presented recently 10 – 12 . Conversely, laser-driven protons can offer many opportunities in this field 13 , in particular when benefitting from their high particle flux that provides ideal conditions for performing and analyzing stress tests on different materials that are exposed to high-energy fluence, i.e., harsh conditions.…”