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Collective Absorption Dynamics and Enhancement in Deformed Targets

Hartmut Ruhl·Peter Mulser·Steffen Hain·Fulvio Cornolti·Andrea Macchi
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Abstract

The interaction of intense fs laser pulses with thin foils that have an imposed deformation is compared with thick targets that develop bow shocks. Both target types yield good absorption. Up to 80% absorption is obtained for a $0.2μm$ thick, 15 times over-dense foil at $4 \cdot 10^{18} W/cm^2$. A value of 50% is obtained for a $4 μm$ thick, 2 times over-dense thick target at $10^{18} W/cm^2$. For comparable extension and curvature of the laser-plasma interfaces absorption levels in both targets become similar. In both absorption scales weakly with intensity and density. Energy transport in thin foils and thick targets, however, is different.

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Hartmut Ruhl, Peter Mulser, Steffen Hain, Fulvio Cornolti, Andrea Macchi. 1998-08-28. Collective Absorption Dynamics and Enhancement in Deformed Targets. https://arxiv.org/abs/physics/9808039

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