Abstract

High-order harmonics generation in rare gases is one of the most rapidly developing topics in the physics of atoms interacting with intense laser pulses [1]. At long wavelength and high intensity, high-order harmonic generation involves the excitation of electrons to the continuum and rescattering from the parent ion [2,3]. This implies a close relationship between harmonic generation and ionisation. Ionization actually influences the harmonic production through depletion of the ground state and defocusing of the fundamental beam caused by the free electrons.

© 1997 Optical Society of America