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Phase diagram of 3D ANNNI model in an effective-field approximation

Anton Šurda
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Abstract

An effective-field method for caculation of thermodynamic properties of three-dimensional lattice spin models is developed. It is applied to the ANNNI model on the simple cubic lattice. The phase diagram of the model, consisting of a large number of commensurate phases and of an incommensurate phase, is calculated, confirming the results of previous approaches. The phase transition lines for a number of commensurate structures are localized, and a strong evidence for absence of the direct phase transition between commensurate phases and the disordered phase is found.

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Anton Šurda. 2003-08-26. Phase diagram of 3D ANNNI model in an effective-field approximation. https://arxiv.org/abs/cond-mat/0308014

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