2009/02/12 by Yoshihiro Nishiyama
Physics and Astronomy · #Advanced Condensed Matter Physics #Physics of Superconductivity and Magnetism #Theoretical and Computational Physics #cond-mat.stat-mech
paper · pdf · doi:10.1103/physrevb.79.054425
published as Phys. Rev. B 79 (2009) 054425.
arxiv created 2009/02/12 · openalex publication_date 2009/02/20 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The spatially anisotropic triangular antiferromagnet is investigated with the numerical diagonalization method. As the anisotropy varies, the model changes into a variety of systems such as the one-dimensional, triangular, and square-lattice antiferromagnets. Taking into account such a geometrical character, we impose the screw-boundary condition, which interpolates smoothly the one- and two-dimensional lattice structures. Diagonalizing the finite clusters with N=16,20,…,32 spins, we observe an intermediate phase between the valence-bond solid (VBS) and N'eel phases. Suppressing the intermediate phase by applying the ring exchange, we realize a direct VBS-N'eel transition. The simulation data indicate that the transition is a continuous one with the correlation-length critical exponent \ensuremathν=0.80(15). These features are in agreement with the deconfinement-criticality scenario advocated by Senthil and co-workers in the context of the high-temperature superconductivity.