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Absorption of intense femtosecond laser pulses in targets having either self-generated or imposed deformations is investigated with Vlasov simulations. Absorption attains high values and scales strongly with the deformation depth but weakly with density and intensity. Fast electron transport is mainly lateral for thin foils with small ratios of target thickness to deformation depth. For thick foils with larger ratios a single magnetic channel forms.

The generation of electron surface oscillations in overdense plasmas irradiated at normal incidence by an intense laser pulse is investigated. Two-dimensional (2D) particle-in-cell simulations show a transition from a planar, electrostatic oscillation at $2\omega$, with $\omega$ the laser frequency, to a 2D electromagnetic oscillation at frequency $\omega$ and wavevector $k>\omega/c$. A new electron parametric instability, involving the decay of a 1D electrostatic oscillation into two surface waves, is introduced to explain the basic features of the 2D oscillations. This effect leads to the rippling of the plasma surface within a few laser cycles, and is likely to have a strong impact on laser interaction with solid targets., Comment: 9 pages (LaTeX, Revtex4), 4 GIF color figures, accepted for publication in Phys. Rev. Lett