Laser-induced breakdown spectroscopy (LIBS) was used as a method to monitor the evolution of C, hydrogen-α, carbon–carbon, and carbon–nitrogen spectral emissions from atmospheric recombination in a ...specific set of organic materials. Ablated samples were composed of a series of linear chain dicarboxylic acids with two to seven C atoms. Accumulated pulses of a focused neodymium-doped yttrium aluminum garnet (Nd:YAG) Q-switched laser beam operated at 532 nm generate a plasma in air at the sample surface. In this work, a dual-pulse LIBS technique was used to improve signal strength by enhancing the nanosecond LIBS plasma with CO2 transverse-excited breakdown in atmosphere laser pulses with an operating wavelength of 10.6 μm. Through a time-resolved analysis, we demonstrate the correlation between the signal strength of selected emissions and the number of C atoms in the linear chain. We also illustrate the effects that these constraints, along with the presence of a chiral C in the chain, have on the peak intensities of the individual lines with respect to each other by comparing the increase or nonexistence of certain spectral lines as we increase the number of C atoms in the linear chain.
Hot electrons created by short, intense laser pulses can heat solid density material to temperatures of order 500 eV. Inertial confinement can maintain such hot-dense plasmas for times of order ...10 ps. This provides a platform for measurement of basic properties of hot dense matter, such as opacity and equation-of-state. In this paper we describe the role of computational modeling in the design and analysis of such opacity experiments. We describe a method to model the hot electron transport and deposition and the resulting target radiation-hydrodynamics. We present several design concepts to achieve uniform, long-lasting plasmas.
Stable coherent beam combining is demonstrated with a high-precise phase control. We developed afeedback program based on new algorism for a filled-aperture coherent beam combining. Four beamswere ...coherently combined by using the developed program. A coefficient of variation (C.V.) of thecombined beam power was less than 0.78%.
Laser ablation of solid targets by Ti:sapphire laser radiation is studied. The targets are irradiated by 150 fs–5 ns laser pulses with a fluence in the range of several J/cm2. Measurements on the ...ablation depth yield an effective penetration depth higher than the optical penetration depth. Advantages and potentials of sub-picosecond laser radiation for the ablation and for the microstructuring of metals are demonstrated.
Laser ablation of solid targets by Ti:sapphire laser radiation is studied. The solid targets are irradiated by 0.2–5000 ps laser pulses in the intensity range of
10
9 − 5 × 10
16
W
cm
2
. Dependences ...of the ablation depth on the laser pulse energy and pulse duration are discussed. Advantages of sub-picosecond laser radiation for precise material processing are demonstrated.
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