Electromagnetic response in dipole superfluids

Abstract

Abstract The Meissner effect is a hallmark of superconductivity arising from the interplay between charged superfluids and electromagnetic fields. However, superfluidity can also occur in systems of charge-neutral particles with magnetic or electric dipole moments, such as Bose-Einstein condensates of magnons or excitons. Despite this interest, the electromagnetic response of dipole superfluids, including potential analogues or contrasts to the Meissner effect, remains poorly understood. Here we develop a Ginzburg-Landau theory to describe dipole superfluids subjected to a pseudo-magnetic field, which is induced by a spatially modulating electromagnetic field. In magnetic dipole superfluids, the response differs strikingly from the conventional Meissner effect: the external field is enhanced by a positive feedback, forming a vortex lattice separated by singular domain walls with diverging electric charges. In contrast, electric dipole superfluids exhibit screening akin to superconductors, where the pseudo-magnetic field is suppressed except near vortices.