Abstract

Compared to a hypothetical two-level atom, the sodium atom has a more complex structure with both Zeeman and hyperfine levels. When an assembly of such atoms is illuminated by a pulse train, the excitation is made more complex by the phenomenon of optical pumping. It is well known that pro longed excitation of the ²S_1/2 - ²P_3/2 transition by circularly polarized light leads to a steady state in which the atoms oscillate exclusively between the F = 2, M_F = 2 ground level and the F = 3, M_F = 3 excited level. The pumping is comparatively slow, so the temporal behavior is important, and the steady state may not be attained in practice. The dynamics of this process will be explained.

© 1990 Optical Society of America