Optical Pumping in Translation Space

Abstract

Perhaps the broadest overall trend in the art of experimental atomic spectroscopy has been the steady development of techniques to obtain more control of the atoms under study. After the discharge was replaced by the molecular beam to improve the control over the translational degrees of freedom, the Stern-Gerlach magnet was developed to select the internal degrees of freedom. This led immediately to the demonstration that the internal degrees of freedom were discretely quantized, and eventually to the discovery of resonance techniques. In the context of this discussion resonance may be viewed as a tool to change the internal quantum state. The development of the separated oscillatory field method opened (prematurely) the field of coherent spectroscopy, which allows, in principle, the preparation of any coherent superposition of the internal states. In addition, the coherences between internal states of different atoms may depend on the atom’s spatial coordinate or velocity.