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arXiv · 0812.3574

Interplay of anisotropy and frustration: triple transitions in a triangular-lattice antiferromagnet

P. -É. Melchy·M. E. Zhitomirsky
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Abstract

The classical Heisenberg antiferromagnet on a triangular lattice with the single-ion anisotropy of the easy-axis type is theoretically investigated. The mean-field phase diagram in an external magnetic field is constructed. Three finite-temperature Berezinskii-Kosterlitz-Thouless transitions are found by the Monte Carlo simulations in zero field. The two upper transitions are related to the breaking of the discrete ${\mathbb Z}_{6}$ symmetry group, while the lowest transition is associated with a quasi-long-range ordering of transverse components. The intermediate collinear phase between first and second transitions is the sliding phase predicted by J. V. José {\it et al}. [Phys. Rev. B {\bf 16}, 1217 (1977)].

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P. -É. Melchy, M. E. Zhitomirsky. 2009-08-24. Interplay of anisotropy and frustration: triple transitions in a triangular-lattice antiferromagnet. https://doi.org/10.1103/physrevb.80.064411

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