Journal of the Physical Society of Japan
Thermodynamic Properties of Antiferromagnetic QuantumXY-Model on the Triangular Lattice
Shigeo Homma, Hirotsugu Matsuda, N. Ogita, Kazuhiro Sano
Abstract
Thermodynamic properties of antiferromagnetic quantum X Y -model ( s =1/2) on a triangular lattice are studied by the Decoupled Cell Monte Carlo Method (DCM). The decoupled cell (DC) used in this study consists of 7 spins. The size N of systems are 15 * 15, 30 * 30, 45 * 45, respectively. Detailed studies of spin pair correlation functions for both x - and z -components are performed at various temperatures. The results suggest that the existence of the shortrange three sublattice structure. The mean square magnetization of a sublattice for the x -component does not depend on N , whereas that of the z -component shows a strong dependence on N below a certain temperature.