Target holder as a specific sensor for laser-induced plasma ablation

Highlights: • Galvanic grounding and isolation of the target from the vacuum chamber have different effects on plasma properties. • Voltage generated on the isolated target can significantly affect the plasma phase after the laser interaction. • Target grounding can cause reduction in ion emissions, as observed for heavier elements. We have used grounded and isolated targets to measure currents of electrons escaping the pulsed laser-produced plasma. Presented experiments show that the laser-produced plasma is dominated by three phases such as the ignition phase, active and afterglow phases. The last two phases occurring after laser-plasma interaction are influenced by whether the target is isolated from the vacuum chamber or grounded. The voltage arising on the isolated target, which acts as a capacitor, mainly affects the active phase, where collisions of particles still form the plasma. This can cause reduction in ion emissions, as observed for heavier elements. The target charging accompanying the laser ablation was driven by nanosecond laser radiation with fluence ranging between 1–4 J/cm².