We analyze the excitation of atoms by intense pulsed laser fields and describe the formation of spatially extended wave packets and substantial inhibition of ionization. A number of physical effects lead to inhibited ionization: We establish through a combination of numerical and analytical methods that one such effect is Raman mixing of intermediate Rydberg levels.

• Received 20 July 1990

DOI:https://doi.org/10.1103/PhysRevLett.66.301