Xg. He et Bhj. Mckellar, Topological effects, dipole moments, and the dual current in 2+1 dimensions - art. no. 022102, PHYS REV A, 6402(2), 2001, pp. 2102
We study the Aharonov-Casher effect and its electromagnetic-dual effect, in
troduced by He, McKellar, and Wilkens, in 2 + 1 dimensions. In this restric
ted space these effects are the result of the interaction of the electromag
netic field tensor with the dual of a current. Transferring the dual operat
ion from the current to the field tensor shows that this interaction may be
reinterpreted as due to the interaction of an effective vector potential a
nd a current. and the topological effects follow immediately. The restricti
on to 2 + 1 dimensions, with this interpretation, provides a unified way of
treating these topological effects for an arbitrary spin, and a general pr
oof for this case is provided. Perhaps more interestingly the treatment sho
ws that a spin-0 particle can show these effects, although it has no magnet
ic or electric dipole moment in the usual sense.