Essentially nonequilibrium steady state of atoms in an optical field

The kinetics of atoms in the monochromatic field of a standing wave has been considered taking into account the recoil effects that appear under the interaction of the atoms with photons of the field. It has been shown that the steady-state solution of the kinetic equation for the atomic density matrix can have considerable asymmetry in the phase space. There is also asymmetry in the fluxes of atoms in the ground and excited states, predominantly near the nodes of the optical field.