Geometric Phase Optics
  We introduce, and propagate wave-packet solutions of, a single qubit system in which geometric gauge forces and phases emerge. We investigate under what conditions non-trivial gauge phenomena arise, and demonstrate how symmetry breaking is an essential ingredient for realization of the former. We illustrate how a "magnetic"-lens, for neutral atoms, can be constructed and find application in the manipulation and interferometry of cold atoms. 
B. Zygelman
quant-ph