Nanoparticles Formed in Picosecond Laser Argon Crystal Interaction
نویسندگان
چکیده
In this work, Molecular Dynamics simulations are conducted to attain thermal and mechanical characteristics of nanoparticles formed in laser materials interaction. It reveals that nanoparticles originate from intense vapor phase explosion. A gas-like structure is observed in nanoparticles in the initial stage of formation. After a short time of evolution, a typical liquid structure is revealed in particles. As a direct consequence of atoms escaping from the particle surface, the temperature of nanoparticles reduces to an undercooling point from the initial super-heating state. Furthermore, it indicates that movements of nanoparticles are dominated by those normal to the target surface. @DOI: 10.1115/1.1621898#
منابع مشابه
Molecular Dynamics Simulation of Heat Transfer and Phase Change During Laser Material Interaction
In this work, heat transfer and phase change of an argon crystal irradiated by a picosecond pulsed laser are investigated using molecular dynamics simulations. The result reveals no clear interface when phase change occurs, but a transition region where the crystal structure and the liquid structure co-exist. Superheating is observed during the melting and vaporizing processes. The solid-liquid...
متن کاملPhase change and stress wave in picosecond laser–material interaction with shock wave formation
When background gas is present in pulsed laser– material interaction, a shock wave down to the nanoscale will emerge. The background gas will affect the phase change and explosion in the target. This study is focused on the void dynamics and stress wave in a model material (argon crystal) under picosecond pulsed laser irradiation. Our results show that existence of ambient gas and the shock wav...
متن کاملTwo mechanisms of nanoparticle generation in picosecond laser ablation in liquids: the origin of the bimodal size distribution.
The synthesis of chemically clean and environmentally friendly nanoparticles through pulsed laser ablation in liquids has shown a number of advantages over conventional chemical synthesis methods and has evolved into a thriving research field attracting laboratory and industrial applications. The fundamental understanding of processes leading to the nanoparticle generation, however, still remai...
متن کاملPhotorefractive effect generated in sillenite crystals by picosecond pulses and comparison with the quasi-continuous regime
Photorefractive gratings are generated in a BSO crystal by the interference of two 25-psec pulses at 532 nm. The grating is analyzed by diffraction of a third pulse or a weak cw argon laser, which permits a continuous monitoring of its evolution from picoseconds to milliseconds. The grating builds up in two steps; their relative contributions vary strongly with fluence. This behavior is explain...
متن کاملPicosecond UV laser induced morphological, biochemical and biological changes in Bombyx mori
Background: In the light of various applications of UV laser in biological system, we have investigated the effect of picosecond UV laser radiation on silkworm Bombyx mori. Materials and Methods: The eggs of NB4D2 of different stages were exposed to pico second pulse laser at 355 nm from Nd:YAG laser for different durations. Results: Due to irradiation alterations in crescent larval body...
متن کامل