A model for nanoparticles synthesis by pulsed laser evaporation

A one-dimensional model of nanoscale particle formation by the exposure of solid targets to millisecond laser pulses of about 10(4)-10(5) W cm(-2) ene rgy density Bur is proposed. A 'soft' regime of vapour diffusion from a las er-heated surface into an ambient atmosphere is studied. Laser flux is pres umed to be relatively low so that the surface temperature does not exceed t he boiling point. Heat transport in the solid, liquid and gas phases, and e vaporation and vapour diffusion in ambient atmosphere are analysed. The nuc lei formation and growth rates are estimated and size distributions of synt hesized nanoparticles are found. The influence of operating conditions, suc h as ambient gas pressure, laser pulse duration and properties of target ma terial, on mean particle size is studied.