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Chiral fluctuations in triangular antiferromagnets at $T \ll T_N$

A. V. Syromyatnikov
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Abstract

Chiral fluctuations in triangular antiferromagnets (TAFs) at $T \ll T_N$ are studied theoretically. The case of a ferromagnetic interaction along c axis (which is directed perpendicular to the plane of the lattice), Dzyaloshinskii-Moriya interaction ${\bf D}\| c$ and a weak magnetic field ${\bf H}\| c$ is considered in detail. Previously, this model has been proposed to describe quantum TAF CsCuCl$_3$. Expressions for dynamical chirality (DC) are derived within the linear spin-wave approximation. In contrast to non-frustrated antiferromagnets, DC is found to be nonzero even at $D,H=0$ in a one-domain sample. We argue that this unusual behavior stems from the fact that a ground state of XY and Heisenberg TAFs is characterized by an axial vector along which DC is directed.

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A. V. Syromyatnikov. 2005-07-29. Chiral fluctuations in triangular antiferromagnets at $T \ll T_N$. https://doi.org/10.1103/physrevb.71.144408

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