Measurement of the ablated thickness of films in the launch of laser-driven flyer plates

Laser-driven flyers were launched from substrate-backed aluminium films. Th e flyers were approximately 1 mm in diameter and a few micrometres thick an d were produced by single pulses from a Q-switched Nd:YAG laser, of 10 ns f ull-width half-maximum and typically up to a few hundred millijoules energy . The ablated thickness of the film was measured using photo-emission spect roscopy to detect file vaporized tracer material in the laser-induced plasm a: tracer layers of yttrium were deposited within the aluminium films at va rious depths, with sub-micrometre accuracy. Using this technique, the ablat ion depths were measured to be between 280 and 1100 nm for laser pulse ener gies between 50 and 156 mJ.