RAMSEY-TYPE SPECTROSCOPY OF ALKALI SPIN COHERENCE IN SEALED GLASS CELLS - MEASUREMENT OF GEOMETRIC QUANTUM PHASES

We report on the detection of ground state spin coherence in coated sp herical, cylindrical, and toroidal sealed glass cells by pump/probe ex periments, where the pump and probe region may be spatially separated. This constitutes an atomic beam situation for the sub-ensemble of ato ms which enters the detection region after having left the pump region . The dependence of the recorded spin signals on the optical frequenci es of the pump and probe lasers are discussed and simulated by Monte-C arlo calculations involving the effect of wall collisions. As a first application the measurement of topological phase changes of spin quant um states due to a rotation of the magnetic field direction along the path of flight are reported.