/pdf/laser-ablation-for-analytical-sampling-what-can-we-learn-1ro1qr2fjg.pdf

Laser ablation for analytical sampling: what can we learn from modeling?

The pulsed laser deposition is a new technique for the growth of thin films,which has been attended generally by people recently The physical principle, unique characteristics and the proceeding of the study were introduced briefly In addation, the result of the PtSi nanometer thin film based on silicon prepared by the pulsed laser deposition was describedPULS

Pulsed laser deposition of thin films

Effect of laser parameters on laser ablation and laser-induced plasma formation: A numerical modeling investigation

We investigated spatio-temporal evolution of ns laser ablation plumes at atmospheric pressure, a favored condition for laser-induced breakdown spectroscopy and laser-ablation inductively coupled plasma mass-spectrometry. The 1064 nm, 6 ns pulses from a Nd:YAG laser were focused on to an Al target and the generated plasma was allowed to expand in 1 atm Ar. The hydrodynamic expansion features were studied using focused shadowgraphy and gated 2 ns self-emission visible imaging. Shadowgram images showed material ejection and generation of shock fronts. A secondary shock is observed behind the primary shock during the time window of 100-500 ns with instabilities near the laser cone angle. By comparing the self-emission images obtained using fast photography, it is concluded that the secondary shocks observed in the shadowgraphy were generated by fast moving target material. The plume front estimates using fast photography exhibited reasonable agreement with data obtained from shadowgraphy at early times ≤400 n...

Experimental and computational study of complex shockwave dynamics in laser ablation plumes in argon atmosphere

A one-dimensional gas-dynamic model is presented for the laser ablation of Cu and the expansion of the Cu vapor in a background gas (He) at 1atm. The ionization of Cu and He, the inverse bremsstrahlung absorption processes and photoionization process, and the back flux onto the target are considered simultaneously. The binary diffusion, the viscosity, and the thermal conduction including the electron thermal conduction are considered as well. Numerical results show that the consideration of ionization and laser absorption in the plume greatly influences the gas dynamics. The ionization of Cu enables the recondensation at the target surface to happen even during the laser pulse. The ionization degree of Cu and He may change greatly with the location in the plume. For laser irradiances ranging from 2to9×1012W∕m2, the simulations show that the second-order ionization of Cu competes with the first-order ionization. In the region close to the target surface, the first-order ionization of Cu dominates. In the c...

Laser ablation of Cu and plume expansion into 1 atm ambient gas

W. R. Meier, J. F. Latkowski, R. P. Abbott, S. Reyes, R. W. Moir, J. Yuan, G. A. Moses, Z. Gui, G. L. Kulcinski, P. F. Peterson, J. Freeman, P. Bardet, C. Debonnel, G. Fukuda, H. Zhao, D. Olander, M. Abdou, A. Ying, N. Morley, P. Calderoni, A. Konkachbaev, A. Elias, M. Ni, T. Sketchley, S. G. Durbin, M. Yoda, S. I. Abdel-Khalik, D. Goodin, A. Nobile, R. Petzoldt, B. Vermillion, G. Besenbruch, J. Maxwell, M. S. Tillack, F. Najmabadi, A. R. Raffray, S. S. Harilal, C. V. Bindhu, A. C. Gaeris, M. R. Zaghloul, J. O'Shay, K. Sequoia

/pdf/progress-in-inertial-fusion-energy-technology-june-september-4lgk8uf79f.pdf

A. C. Gaeris

Papers

Progress in Inertial Fusion Energy Technology: June - September 2003