TOPOLOGICAL PHASE-SHIFT IN A COLD-ATOM INTERFEROMETER

Matter-wave interferences in a four-pulse version of a Ramsey-Borde at om interferometer have been utilized to study phase shifts. A topologi cal phase shift analogous to the scalar Aharonov-Bohm effect proposed for charged-particle interferences in the presence of a pulsed electro static potential has been investigated. The time-dependent potential h as been generated by the interaction of a laser field with an induced atomic dipole without spatial variation along the interferometer arms. The atom interferometer has been run with laser-cooled magnesium atom s stored in a magneto-optical trap.