Permanent Electric Dipole Moment of an Rb Atom

Abstract

We experimentally determine the conjecture that hydrogen-like atomssuch as Rb and Cs may have large permanent electric dipole moments(EDMs). The saturated Rb vapour fills a cylindrical capacitor inthe experiment. The influence of the vapour dielectric medium oncapacitance is measured with a digital capacitance meter. Supposingthat the measurement influence comes from the permanent EDMs of Rbatoms, from the experimental result we find that the EDM is large,i.e. dRb⩾8.6e×10-9 cm.