2002/11/14 by C. H. Chung, Chi-Jui Chung, Hae‐Young Kee +2 · 2 citations
Physics and Astronomy · #Advanced Condensed Matter Physics #Physics of Superconductivity and Magnetism #Theoretical and Computational Physics #cond-mat.str-el
paper · pdf · doi:10.1103/physrevb.67.224405
published as Phys. Rev. B 67, 224405 (2003) · 14 pages, 17 figures
arxiv created 2002/11/14 · openalex publication_date 2003/06/10 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We study the effect of four-particle ring exchange process on an orbital antiferromagnetic state that occurs in some correlated electron systems in two dimensions. The primary question is whether the ring exchange process enhances or suppresses the orbital antiferromagnetic ordering. Using the fact that the orbital antiferromagnetic state arises in the large-N limit of the SU(N) generalization of the t\ensuremath-J model, we consider the large-N limit of the t\ensuremath-J\ensuremath-K model where K represents the four-particle ring exchange term. The phase diagrams in the large-N mean-field theory are obtained for the half-filling and finite hole concentrations at zero temperature. It is found that the ring exchange in general favors dimerized states or the inhomogeneous orbital antiferromagnetic state and suppresses the homogeneous orbital antiferromagnetic state. We compare our results with other related models of strongly correlated systems with ring exchange processes.