Ponderomotive ion acceleration in dense plasmas at super-high laser intensities N. Naumova, T. Schlegel, V. T. Tikhonchuk, C. Labaune, I. V. Sokolov and G. Mourou Eur. Phys. J. D, 55 2 (2009) 393-398 Published online: 19 September 2009 DOI: 10.1140/epjd/e2009-00250-2