Field-induced Kosterlitz-Thouless transition in critical triangular-lattice antiferromagnets

Abstract

In this paper, we directly obtain from Monte Carlo simulations the critical magnetic field H = 0.29(3) of the field-induced Kosterlitz-Thouless transition in the critical triangular-lattice antiferromagnet. The Yang-Lee zero approach clearly shows the field-induced Kosterlitz-Thouless transition and the critical magnetic field agrees well with the results from other indirect methods. Also, the reduced zero-field susceptibility gives us the same conclusion. For the investigations, we used the exact and approximate ground densities of states as a function of magnetization by using both the exact enumeration method for small systems (up to 9×9lattices) and the Wang-Landau Monte Carlo algorithm for large systems (up to 30×30lattices). Copyright © 2015 by Walter de Gruyter GmbH.