Plasma Production by Laser Ablation of Heavy Metals

An Nd:YAG focused laser operating at 1064 nm, 3 ns pulse width, 360 mJ pulse energy, is employed to irradiate heavy metals, such as Ta, W, Pt, Au, and Pb. The in-vacuum irradiation produces an expanding plasma at the target surface which has high density, temperature, and kinetic energy of emitted ions. Ions have a velocity of the order of 104 m/s with a charge state up to about 10+ and large ion energy distribution from some eV up to values of the order of some keV. The measurements of the ion emission, their velocity, and energy have been performed using a Faraday cup ion collector connected in time-of-flight (TOF) configuration. The ion energy, charge state, and energy distributions were performed using a cylindrical electrostatic ion deflector (IEA) with high energy resolution. The measurements are investigated and compared with literature and theoretical prediction models.