Aharonov-Casher effect in half-integer spin antiferromagnets

In this paper, the manifestation of the Aharonov-Casher effect in condensed media is considered. In the one-dimensional Hubbard model with arbitrary band filling we derived analytical expressions for the oscillating part of the ground state energy of mesoscopic ring with twisted boundary conditions which model the influence of Aharonov-Bohm (AB) and/or Aharonov-Casher (AC) fields. It is shown that in the limit of strong on-site repulsion AB-oscillations disappear for half-filled band, but the amplitude of the AC-oscillations, on the contrary, attains its maximum. The period of the AC-oscillations in this case equals hc/2μB μB is the Bohr magnetron)