Optimization of the focused flux of high harmonics S. Kazamias, D. Douillet, C. Valentin, Th. Lefrou, G. Grillon, G. Mullot, F. Augé, P. Mercère, Ph. Zeitoun and Ph. Balcou Eur. Phys. J. D, 26 1 (2003) 47-50 Published online: 24 April 2003 DOI: 10.1140/epjd/e2003-00083-y