Renormalization Group Studies of Antiferromagnetic Chains I . * Nearest - Neighbor Interactions
نویسنده
چکیده
The SLAC real-space renormalization group method is used to study one-dimensional antiferromagnetic chains at zero temperature. Calculations using three-site blocks (for the Heisenberg-Ising model) and two-site blocks (for the isotropic Heisenberg model) are compared with exact results. In connection with the two-site calculation a duality transformation is introduced under which the isotropic Heisenberg model is self-dual. Such duality tranformations can be defined for models other than those considered here, and may be useful in various block-spin calculations. (Submitted to Phys. Rev. B) * This work was supported in part by the Department of Energy under contract number DE-AC03-76SF00515, and in part by a National Science Foundation Fellowship.
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