Quantum Phase Transitions in Spin Systems
arXiv:cond-mat/0105517 · doi:10.1142/9789812799760_0022
Abstract
We discuss the influence of strong quantum fluctuations on zero-temperature phase transitions in a two-dimensional spin-half Heisenberg system. Using a high-order coupled cluster treatment, we study competition of magnetic bonds with and without frustration. We find that the coupled cluster treatment is able to describe the zero-temperature transitions in a qualitatively correct way, even if frustration is present and other methods such as quantum Monte Carlo fail.
8 pages, 12 Postscipt figures; Accepted for publication in World Scientific