Dynamics of Kramers-Henneberger atoms in focused laser beams of circular polarization

In intense laser fields, electrons of atoms will follow the laser field and undergo quiver motion just like free electrons but still weakly bound to the atomic core, thus forming a set of specific dressed states named Kramers-Henneberger (KH) states, which comprise the KH atoms. In a focused laser beam, in addition to Ponderomotive (PM) force, KH atoms will experience KH force, which is unique to KH atoms. We examine both PM and KH forces as well as corresponding velocity gain of hydrogen and helium atoms in a focused laser field with circular polarization. We work out laser parameters which can be used in experimental confirmation of circularly polarized KH atoms.