Recent progress in the understanding of high-order harmonic conversion from atoms and ions exposed to high-intensity, short-pulse optical lasers is reviewed. We find that ions can produce harmonics comparable in strength to those obtained from neutral atoms, and that the emission extends to much higher order. Simple scaling laws for the strength of the harmonic emission and the maximum observable harmonic are suggested. These results imply that the photoemission observed in recent experiments in helium and neon contains contributions from ions as well as neutrals.
Publication Source (Journal or Book title)
Proceedings of SPIE - The International Society for Optical Engineering
Schafer, K., Krause, J., & Kulander, K. (1993). High-order harmonic generation with short-pulse lasers. Proceedings of SPIE - The International Society for Optical Engineering, 1860, 190-197. https://doi.org/10.1117/12.147577