Ground state phase diagram of a spin-2 antiferromagnet on the square lattice |
| |
Authors: | H Niggemann A Klümper J Zittartz |
| |
Institution: | Institut für Theoretische Physik, Zülpicher Strasse 77, 50937 K?ln, Germany, DE
|
| |
Abstract: | We use the vertex state model approach to construct optimum ground states for a large class of quantum spin-2 antiferromagnets
on the square lattice. Optimum ground states are exact ground states of the model which minimize all local interaction operators.
The ground state contains two continuous parameters and exhibits a second order phase transition from a disordered phase with
exponentially decaying correlation functions to a Néel ordered phase. The behaviour is very similar to that of the corresponding
ground state of a quantum spin-3/2 model on the hexagonal lattice, which has been investigated in an earlier paper.
Received 8 April 1999 |
| |
Keywords: | PACS 75 10 Jm Quantized spin models - 05 50 +q Lattice theory and statistics (Ising Potts etc ) |
本文献已被 SpringerLink 等数据库收录! |