The AharonovCasher Effect for Particles of Arbitrary Spin.pdf

hep-ph/9710433 7 9 9 The Aharonov-Casher Effect 1 t for Particles of Arbitrary Spin ∗ c O 2 2 Ya.I.Azimov a, R.M.Ryndin b 1 Petersburg Nuclear Physics Institute v 3 Gatchina, St.Petersburg, 188350, Russia 3 e-mail: a azimov@pa1400.spb.edu, 4 0 b ryndin@thd.pnpi.spb.ru 1 7 9 / h p - Abstract p e h The Aharonov-Casher (AC) effect for quantum motion of a neutral mag- : v netized particle in the electric field is believed to be a topological effect closely i related to the known Aharonov-Bohm (AB) effect. We study how it depends X r on the spin of the particle involved. Duality of the AB and AC effects is a demonstrated to exist only for two extreme spin (and magnetic moment) pro- jections. Classical consideration confirms the conclusion. Motion of a classical mag- netized particle with generally oriented magnetic moment in the AC field appears to be subjected to both forces and torques. Only for two special ori- entations of the magnetic moment (same as in the quantum case) the motion is effectively free and similar to the AB motion of a charged particle. Thus, the AC effect is not really topological. Presence of higher multipoles totally destroys the possible AB-AC duality. 1. The Aharonov-Bohm effect (ABE) [1], the first example of purely topological