We predict a quantum phase shift of a moving electric dipole in the presence of an external magnetic field at a distance. On the basis of the Lorentz-covariant field interaction approach, we show that a phase shift appears in the internal dipole state under the condition that the dipole is moving in the field-free region, which is distinct from the topological He-McKellar-Wilkens phase generated by a direct overlap of the dipole and the field. We discuss the experimental feasibility of detecting this phase with atomic interferometry and argue that detection of this phase will resolve the question of the locality in quantum electromagnetic interaction.
The force on and the energy of a ''di-monopole'', which is the limiting case of a dipole made from two monopoles at zero separation and finite magnetic moment, interacting with an externally fixed magnetic field resulting from an electric current, is considered. A model involving only a monopole is used to illustrate the physical principles involved when magnetic sources move in a solenoidal field whose source is an electric current. The problems encountered in Hamiltonian theory are discussed. 5 refs., 3 figs. (LEW)
The effects of combined external electric and magnetic fields on elastic collisions in ultracold Li-Rb mixtures are studied using recently obtained experimentally verified potentials. Our analysis provides both quantitative predictions for and a detailed physical interpretation of the phenomena arising from electric-field-induced interactions. It is shown that the electric field shifts the positions of intrinsic magnetic Feshbach resonances, generates copies of resonances previously restricted to a particular partial-wave collision to other partial-wave channels, and splits Feshbach resonances into multiple resonances for states of nonzero angular momenta. It was recently observed that the magnetic dipole-dipole interaction can also lift the degeneracy of a
p-wave state splitting of the associated
p-wave Feshbach resonance into two distinct resonances at different magnetic fields. Our work shows that the splitting of the resonances produced by an applied electric field is more than 1 order of magnitude larger. This phenomenon offers a complementary way to produce and tune an anisotropic interaction and to study its effect on the many-body physics of heteronuclear atomic gases.