The Aharonov-Bohm effect in neutral liquids

The Aharonov-Bohm effect was discovered as a quantum-mechanical effect for charged particles, but it has its counterpart in classical wave mechanics. The Aharonov-Bohm interference arises at the scattering of a sound wave by a vortex in classical and quantum hydrodynamics. This interference leads to a transverse force between quasiparticles and vortices in superfluids and superconductors. The Aharonov-Bohm effect was also generalized to neutral particles with magnetic or electric dipole momenta. The Aharonov-Bohm effect for charge particles and its modification for magnetic momenta (the Aharonov-Casher effect) have already been experimentally observed, and the efforts to detect the Aharonov-Bohm effect for electrically polarized neutral particles are on the way. A possible system for this detection is a Bose-condensate of excitons in a double quantum well. Observation of the Aharonov-Bohm effect in this system would provide direct evidence of Bose-Einstein condensation.