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Quantum Fluctuations in the Annni Model

A. B. Harris·C. Micheletti·J. M. Yeomans
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Abstract

We obtain the ANNNI model from a Heisenberg model with large single--ion anisotropy energy, $D$, as might be relevant for helical spin systems. We treat quantum fluctuations to lowest order in $1/S$ at zero temperature within an expansion in $J/D$, where $J$ is an exchange energy. The transition from the state with periodicity $p=4$ to the uniform state ($p= \infty$) occurs via an infinite sequence of first order transitions in which $p$ increases monotonically.

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A. B. Harris, C. Micheletti, J. M. Yeomans. 1994-11-28. Quantum Fluctuations in the Annni Model. https://arxiv.org/abs/cond-mat/9411117

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