We report on the recent progress in theoretical and experimental understanding of harmonic generation by intense laser pulses. The paper will focus on the role of dynamically induced phase of the atomic polarization in the processes of harmonic generation by individual atoms, as well as harmonic propagation and phase matching in macroscopic media.
Antoine, P., Gaarde, M., Salieres, P., Carre, B., LHuillier, A., & Lewenstein, M. (1997). On the phase of atomic polarization in harmonic generation processes. Institute of Physics Conference Series (Online), 154, 142-159. https://hdl.handle.net/2078.5/143894 (Original work published 1997)