The spin-1/2 alternating Heisenberg model with XY-like anisotropy is studied by numerical methods. This model exhibits critical behavior in the ground state as the bond-alternation parameter δ approaches 0. The critical exponents characterizing this ground-state critical point are estimated. The results agree well with those of the analytical calculation of Nakano and Fukuyama. A logarithmic correction of the type predicted by Black and Emery is found to be consistent with numerical data in the isotropic Heisenberg model but not in anisotropic models.
ASJC Scopus subject areas
- Physics and Astronomy(all)