LASER induced breakdown spectroscopy (LIBS) has been used for the quantitative analysis of Cu–Ni alloy of known composition (75% Cu, 25% Ni) using the one line calibration free-LIBS (OLCF-LIBS), self-calibration-LIBS (SC-LIBS), calibration free LIBS (CF-LIBS), time of flight-mass spectroscopy (TOF-MS), energy dispersive X-ray spectroscopy (EDX) and X-ray fluorescence spectroscopy (XRF). For the LIBS-based studies, the plasma was generated by focusing the beam of a Q-switched Nd:YAG laser (532 nm, pulse energy about 200 mJ, 5 ns pulse duration) while the sample was placed in air at an atmospheric pressure. Plasma temperature about (9500 ± 300) K was calculated by the Boltzmann plot method using the neutral lines of Cu and Ni whereas the electron number density was calculated (2.0 ± 0.5) × 10¹⁶ cm⁻³ from the Stark broadening of an isolated Cu line as well as using the relative intensities of the neutral and singly ionized optically thin lines in the Saha–Boltzmann equation. The elemental compositions determined by different LIBS methods and standard techniques are; OLCF-LIBS (69% Cu and 31% Ni), SC-LIBS (72% Cu and 28% Ni), CF-LIBS (74% Cu and 26% Ni), TOF (74% Cu and 26% Ni), EDX (75% Cu and 24.5% Ni), XRF (73% Cu and 24.7% Ni), and LA-TOF (74% Cu and 26% Ni). It is demonstrated that the CF-LIBS method gives compositions comparable with that determined by LA-TOF, EDX, or XRF, which is also in agreement with the certified reported composition.

The ablation of calcium sample has been studied by the optical emission spectroscopy of the evolving plasma using the fundamental, second, and third harmonic of a Nd:YAG laser, which reveals numerous transitions due to neutral and singly ionized calcium. The measurements have been performed to determine the electron temperature and electron number density and their spatial behavior. In addition, the behavior of the electron temperature and number density as a function of laser irradiance and ambient gas pressure has been studied. The processes of laser photon absorption in the plasma through inverse bremsstrahlung and photoionization have also been discussed.

We present optical emission studies of the laser ablation brass plasma generated by the fundamental, second, and third harmonics of a neodymium doped yttrium aluminum garnet laser. The spectra predominantly reveal the spectral lines of the neutral and singly ionized copper and zinc. The excitation temperatures are determined by the Boltzmann plot method, whereas the electron number densities have been extracted from the Stark broadened line profiles. The spatial variations in the spectral line intensities and the plasma parameters at 1000, 500, and 100 mbar air pressures have been evaluated. Besides, the effect of the ambient gases (He, Ne, and Ar), the laser irradiance, and the laser wavelengths on the plasma parameters have been investigated.

Lithium isotope separation has been achieved employing the two-step photoionization technique along with a narrow band dye laser in conjunction with a time of flight mass spectrometer. The demonstrated method yields a high degree of selectivity by tuning the dye laser at the resonance levels of ${\mathrm{Li}}^6$ and ${\mathrm{Li}}^7$ . It is inferred that the concentration of the natural abundance of the ${\mathrm{Li}}^6$ isotope gets enhanced up to over 47% as the exciter dye laser is tuned to the ${}^{2}P_{1∕2}$ of ${\mathrm{Li}}^6$ even if the linewidth of the exciter laser is not sufficiently narrow to excite the isotopic level. It is also noticed that the much higher energy density of the exciter laser limits the resolution of the fine structure levels of the lithium isotopes that leads to a loss in the enrichment of ${\mathrm{Li}}^6$ due to the power-broadening effect. Measurements of the photoionization cross section of the lithium isotopes from the $2p{}^{2}P_{1∕2,3∕2}$ , excited states for ${\mathrm{Li}}^6$ and ${\mathrm{Li}}^7$ and the corresponding number densities are reported.