We report experimental results on correlated double ionization of magnesium (Mg) by near-infrared (0.8- and $1.03\text{−}\mu \mathrm{m}$) circularly polarized laser fields. With $0.8\mu \mathrm{m}$, we confirm the recollision interpretation of the observed “knee” structure of Mg [Gillen et al., Phys. Rev. A 64, 043413 (2001)], even though the experiments are performed in the multiphoton regime. Our experiments show that, even in the multiphoton regime, which is normally thought to be a purely quantum-mechanical territory, some ionization phenomena can still be understood classically.

• Received 14 July 2019
• Revised 26 November 2019

DOI:https://doi.org/10.1103/PhysRevA.101.013405