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arXiv · 0901.2336

Spin-Wave Instabilities and Non-Collinear Magnetic Phases of a Geometrically-Frustrated Triangular-Lattice Antiferromagnet

J. T. Haraldsen·M. Swanson·G. Alvarez·R. S. Fishman
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Abstract

This paper examines the relation between the spin-wave instabilities of collinear magnetic phases and the resulting non-collinear phases for a geometrically-frustrated triangular-lattice antiferromagnet in the high spin limit. Using a combination of phenomenological and Monte-Carlo techniques, we demonstrate that the instability wave-vector with the strongest intensity in the collinear phase determines the wave-vector of a cycloid or the dominant elastic peak of a more complex non-collinear phase. Our results are related to the observed multi-ferroic phase of Al-doped CuFeO$_2$.

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J. T. Haraldsen, M. Swanson, G. Alvarez, R. S. Fishman. 2009-01-15. Spin-Wave Instabilities and Non-Collinear Magnetic Phases of a Geometrically-Frustrated Triangular-Lattice Antiferromagnet. https://doi.org/10.1103/physrevlett.102.237204

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