Dynamics of laser-blow-off induced Li plume in confined geometry

Abstract

Dynamics of Li plasma plume created by laser-blow-off technique in air ambient is reported. Plasma plume dynamics and its optical emission are investigated in planar and confined geometries using time resolved shadowgraph imaging and optical emission spectroscopy. Significant differences in the plasma characteristics in confined geometry are quantitatively investigated by comparing the plasma parameters (temperature and density) in free expansion and confined geometry configurations. Dynamics and physical parameters of the primary as well as the reflected shock waves (in confined geometry) and their interactions with expanding plasma are briefly addressed. A large enhancement in the emission intensities of Li I 610.3 nm (2p 2 P 1/2, 3/2 3d 2 P 3/2, 5/2 ) and 670.8 nm (2s 2 S 1/2 2p 2 P 1/2, 3/2 ) is correlated with the shock wave dynamics in the two geometries. Strong self reversal in the neutral emission infers an increase in the population density of neutrals within the confined plasma plume. V C 2013 AIP Publishing LLC.

Effect of focusing plane on laser blow-off shock waves from confined aluminum and copper foils

“…Despite a lot of theoretical [28,[32][33][34][35] and experimental efforts [15-17, 22, 23, 36-40] which elucidated the role of different parameters on blow-off properties, there still exists a few concerns in the LIBO technique. For example, holding the planarity of the flyer which plays a critical role in the determination of shock jump states for accurate EOS generation, acceleration of the flyer to higher velocities and effective coupling of the input laser energy to the foil [15,16] are some of the critical challenges.…”

Effect of magnetic field on the laterally colliding plasma plumes

“…[1,[7][8][9][10] Colliding plasma with different targets, laser parameters, ambient and ablation geometries have been reported by several authors. [11][12][13][14][15][16][17][18][19][20][21][22][23][24] In our earlier work in aluminium colliding plasma we had found a clear distinct interaction zone and neutral emission is significantly enhanced at later times due to increase in three body recombination. [25] Plasma-plasma interaction in the presence of external magnetic field is an interesting phenomenon to study because of its implications from the understanding fundamental physics as well as applications.…”

Effect of cylindrical cavity height on laser-induced breakdown spectroscopy with spatial confinement

“…Among these methods, the additional instrument of the spatial confined LIBS is simple compared with other LIBS systems; the spatial confinement can effectively enhance the emission intensity of LIBS. In the last decade or so, cavities with different shapes (typical examples: a pair of plates [26][27][28], cylindrical cavity [29][30][31], and hemispherical cavity [32][33][34]) are used to confine the laser-induced plasma, and the spectral emission, enhanced by the cavity, is observed and discussed [26,35,36].…”