Variation of magnetic order for the 2-D systems of strongly correlated electrons with external magnetic field

Based on our earlier mean held approach (H. Doh et al., Phys. Rev. B 55 (19 97) 14084), we present the variation of antiferromagnetic (staggered magnet ization) order as a function of external magnetic field for the two-dimensi onal systems of strongly correlated electrons at half-filling. In the prese nt work, we consider both the Zeeman and the Aharonov-Bohm effects in assoc iation with the Hubbard model. It is shown that the local minima of stagger ed magnetization and the undulatory variation of antiferromagnetic order re main unchanged up to a critical magnetic field and temperature. Further, we demonstrate that the Aharonov-Bohm (Berry) effect causes reduction in the critical magnetic field as a consequence of enhanced destruction of the ant iferromagnetic order. (C) 1999 Elsevier Science B.V. All rights reserved.