Laser-wavelength dependence of mass-ablation rate and heat-flux inhibition in laser-produced plasmas

Thin-foil experiments at 1.06, 0.53, and 0.26 μm have been realized in order to measure mass-ablation rate $\dot{m}$ as a function of absorbed laser flux ${\phi }_a$ and laser wavelength $\lambda$. The results can be put in the form $\dot{m}(\mathrm{kg}/\mathrm{s}{\mathrm{cm}}^2)\approx 110{\left[{\phi }_a\frac{(\mathrm{W}/{\mathrm{cm}}^2)}{{10}^{14}}\right]}^{\frac{1}{3}}{\lambda }_{\mu \mathrm{m}}^{-\frac{4}{3}}$. Hydrodynamical simulations of these experiments show that heat-flux inhibition occurs at each wavelength, but the mechanisms are very different.