Investigation of ion dynamics of laser ablated single and colliding carbon plasmas using Faraday cup.

We report a comparative study of a single plasma and a colliding laser produced plasma, investigated using a Faraday cup. An enhancement in ion emission and stagnation is observed in colliding plasma plume compared to single plasma plume. We observed that fast ion generation in laser ablated plasma can be achieved at large laser intensity on to the target.

Stoichiometry of laser ablated brass nanoparticles in water and air.

We report on the stoichiometric analysis of laser ablated brass plasma nanoparticles (NPs) in water and ambient air. Morphological study of the deposited NPs in water showed smaller spherical NPs compared to micrometer sized spherical particles in air. The smaller particles were Zn enriched and the concentration decreased with increases in size.

Stoichiometric investigations of laser-ablated brass plasma.

Laser-ablated brass plasma plumes expanding in various air pressures have been studied using optical emission spectroscopy and two-dimensional imaging. The velocity of the plume front calculated from the R-t plot decreases from 1.9×10(4) m/s to ~5.

Dynamics of laser-ablated carbon plasma: formation of C2 and CN.

We report time-resolved imaging of a laser-ablated carbon plasma plume to investigate the expansion dynamics of C(2) and CN in an ambient atmosphere of nitrogen gas at various pressures. An attempt is made to locate C(2) and CN species in the carbon plasma plume and correlate them with the results of spectroscopic observations. The ablated C(2) and CN species decelerate due to collisions with nitrogen gas and are localized in the slower part (approximately 300 ns) of the expanding plume.

Spectroscopic investigations of carious tooth decay.

We report on the elemental composition of healthy and infected part of human tooth using laser induced breakdown spectroscopy (LIBS). We have used prominent constituent transitions in laser-excited tooth to diagnose the state of the tooth. A nanosecond laser pulse (355nm, 5ns) was used as an ablating pulse and the sodium (3s2S-3p2P) at 588.

Laser-induced gas breakdown and its application to switching.

The effect of laser-produced plasma from a biased metal target in a background gas (argon) is studied. We report that switching of an argon gas discharge is controlled by metal plasma or by polarity of the target.

Gain measurement of Cd recombination lasers.

Gain measurement and characteristics of an IR laser in Cd I at 1.65-microm (4f(3)F(4)-5d(3)D(3)) and 1.43-microm (6p(3)P(1)-6s(3)S(1)) transitions over a range of discharge parameters in a sealed discharge tube, based on a segmented plasma excitation and recombination scheme, are presented.

Pulsed metal-vapor recombination laser.

A visible cadmium-ion recombination laser based on an electron-ion recombination pumping mechanism is reported. Laser oscillation is observed in the 4f (2)F(7/2)-5d(2)D(5/2) and 4f(2)F(5/2)-5d (2)D(3/2) transitions of Cd II over a range of discharge parameters in the presence of low-pressure helium gas in a sealed discharge tube. Laser oscillation in a sealed discharge tube using a simple capacitor discharge is reported for the first time to the authors' knowlege.