Metastable states of atomic hydrogen in an ideal linearly polarized laser have been shown to exist. These states, in the laboratory frame, have the electron oscillating with a large amplitude. The electron will radiate both even and odd harmonics of the laser frequency at a rate calculated here. The electron may also radiate nonharmonic radiation, thereby leaving the atom in an excited state. This process contributes to the width of the ground state. Both processes are evaluated at an upper limit of intensity imposed upon the theory by the dipole approximation.

• Received 9 October 1991

DOI:https://doi.org/10.1103/PhysRevA.46.4209