Ergodicity of the extended anisotropic 1D Heisenberg model: response at low temperatures
نویسندگان
چکیده
We present the results of exact diagonalization calculations of the isolated and isothermal on-site static susceptibilities in the anisotropic extended Heisenberg model on a linear chain with periodic boundary conditions. Based on the ergodicity considerations we conclude that the isothermal susceptibility will diverge as T → 0 both in finite clusters and in the bulk system in two non-ergodic regions of the phase diagram of the system. c © 2008 Elsevier B.V. All rights reserved. PACS: 75.40.C; 71.27; 75.10.D
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