Surface nanostructuring of laser ablated copper in ambient gas atmosphere and a magnetic field

Abstract

A comprehensive study on deposition of copper nanoclusters back on to the laser ablated target in combined ambient of gas and a magnetic field is reported. The characteristics and mechanism of the inverse plume deposition are investigated by characterizing the laser ablated plasma plume using time resolved imaging and optical emission of the plume. The morphology of the deposited particles in presence of magnetic field depends on the nature of the ambient gas used; the elliptical shape of reverse deposited particles changes to spherical with the increase in mass of the ambient gas. The structural, morphological, and optical properties of the deposited nanoclusters were studied by using x-ray diffraction, scanning electron microscope and photoluminescence spectra respectively. The possibility of enhanced deposition rates in combined ambient gas and a magnetic field has potentials of industrial applications of the process.

Dynamics of femto- and nanosecond laser ablation plumes investigated using optical emission spectroscopy

“…40 The decrease in electron density with time for both ns and fs LPP is due to the plasma expansion and three-body recombination of electrons with their parent ions. 30,44,45 Unnikrishnan et al conducted studies on the electron density of copper from a ns LPP and has found that the temporal profile follows an exponential decay. 38 Also, Xu et al conducted temporal studies using fs LPP on a Pb target and also observed exponential electron density decay for fs LPP.…”

Brass plasmoid in external magnetic field at different air pressures

“…Initially, plasma gets energized and the free expansion of the plasma plume results in decrease in conductivity of the plasma according to the relation which in turn decreases the magnetic diffusion time into the plasma causing the polarization of the plasma. 16,26 The electric field E is established perpendicular to both magnetic field (B) and the plasma velocity. The plasma moves across the B field byẼ ÂB drift with velocity ðẼ ÂBÞ=B 2 .…”