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arXiv · 0912.1750

Non-Collinear Magnetic Phases of a Triangular-Lattice Antiferromagnet and Doped CuFeO$_2$

Randy S. Fishman·Satoshi Okamoto
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Abstract

We obtain the non-collinear ground states of a triangular-lattice antiferromagnet with exchange interactions up to third nearest neighbors as a function of the single-ion anisotropy $D$. At a critical value of $D$, the collinear $\uudd $ phase transforms into a complex non-collinear phase with odd-order harmonics of the fundamental ordering wavevector $\vQ $. The observed elastic peaks at $2π\vx -\vQ $ in both Al- and Ga- doped CuFeO$_2$ are explained by a "scalene" distortion of the triangular lattice produced by the repulsion of neighboring oxygen atoms.

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Randy S. Fishman, Satoshi Okamoto. 2009-12-09. Non-Collinear Magnetic Phases of a Triangular-Lattice Antiferromagnet and Doped CuFeO$_2$. https://doi.org/10.1103/physrevb.81.020402

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