Uniaxially anisotropic antiferromagnets in a field on a square lattice

Autor:	Holtschneider, M., Selke, W.
Rok vydání:	2008
Předmět:	Condensed Matter - Statistical Mechanics
Druh dokumentu:	Working Paper
DOI:	10.1140/epjb/e2008-00149-2
Popis:	Classical uniaxially anisotropic Heisenberg and XY antiferromagnets in a field along the easy axis on a square lattice are analysed, applying ground state considerations and Monte Carlo techniques. The models are known to display antiferromagnetic and spin-flop phases. In the Heisenberg case, a single-ion anisotropy is added to the XXZ antiferromagnet, enhancing or competing with the uniaxial exchange anisotropy. Its effect on the stability of non-collinear structures of biconical type is studied. In the case of the anisotropic XY antiferromagnet, the transition region between the antiferromagnetic and spin-flop phases is found to be dominated by degenerate bidirectional fluctuations. The phase diagram is observed to resemble closely that of the XXZ antiferromagnet without single-ion anisotropy. Comment: 8 pages, 9 figures, submitted to Eur. Phys. J. B
Databáze:	arXiv
Externí odkaz:	http://arxiv.org/abs/0801.3217 Zobrazit plný text záznamu View this record from Arxiv