Silver (Ag) plasma has been generated by employing Nd:YAG laser (532 nm, 6 ns) laser irradiation. The energy and flux of ions have been evaluated by using Faraday cup (FC) using time of flight (TOF) measurements. The dual peak signals of fast and slow Ag plasma ions have been identified. Both energy and flux of fast and slow ions tend to increase with increasing irradiance from 7 GW cm−2 to 17.9 GW cm−2 at all distances of FC from the target surface. Similarly a decreasing trend of energies and flux of ions has been observed with increasing distance of FC from the target. The maximum value of flux of the fast component is 21.2 × 1010 cm−2, whereas for slow ions the maximum energy and flux values are 8.8 keV, 8.2 × 1012 cm−2 respectively. For the analysis of plume expansion dynamics, the angular distribution of ion flux measurement has also been performed. The overall analysis of both spatial and angular distributions of Ag ions revealed that the maximum flux of Ag plasma ions has been observed at an optimal angle of ∼15°. In order to confirm the ion acceleration by ambipolar field, the self-generated electric field (SGEF) measurements have also been performed by electric probe; these SGEF measurements tend to increase by increasing laser irradiance. The maximum value of 232 V m−1 has been obtained at a maximum laser irradiance of 17.9 GW cm−2.

The energy and density measurements of laser induced Mg plasma ions have been performed by employing a Faraday cup as an ion collector by using the time of flight method. A Nd:YAG laser (532 nm, 8 ns) has been employed as an irradiation source at irradiances ranging from 4.5 GW/cm2 to 8.1 GW/cm2. For the first time, two distinct peaks of ions with the time delay of ns and μs have been identified for low-Z metal corresponding to fast and slow ions. It is revealed that both the energy and density of Mg plasma ions are increased with increasing laser irradiance and are decreased with the increasing distance between the collector and the target. The density of slow ions is 4–12 times higher than the density of fast ions for the selected irradiances. However, the energy of slow ions is in the range of 100's of eV and the energy of fast ions is in the range of 10's of keV. The anisotropic behavior and forward peaking of plasma are confirmed by the investigation of the angular distribution of ions. The plasma assisted laser ablated morphology is investigated by scanning electron microscopy (SEM) analysis. SEM analysis reveals the formation of cavities, cones, and spikes. The increasing trend of ion density and energy with increasing laser irradiance is correlated with the increased ablated areas and number density of cones.

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