Uniaxially anisotropic antiferromagnets in a field along the easy axis

Selke, W., Holtschneider, M., Leidl, R., Wessel, S., and Bannasch,G.
Institut für Theoretische Physik, Technische Hochschule Aachen, Aachen, Germany;
Department of Physics, Simon Fraser University, Burnaby, BC V5A 1S6, Canada
Institut für Theoretische Physik, Universität Stuttgart, Stuttgart, Germany

Abstract:

Uniaxially anisotropic antiferromagnets in a field along the easy axis are studied with the help of ground state considerations and Monte Carlo simulations. For classical models, the XXZ model as well as variants, we analyze the role of non--collinear spin configurations of biconical or bidirectional type interpolating between the well--known antiferromagnetic and spin--flop structures. Possible experimental applications to layered cuprate antiferromagnets are discussed. Finally, results of quantum Monte Carlo simulations for the $S$=1/2 XXZ model on a square lattice are presented, and compared with previous findings.


cond-mat/0803.0067