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arXiv · 1704.07936

Modulated phases in a three-dimensional Maier-Saupe model with competing interactions

P. F. Bienzobaz·Na Xu·Anders W. Sandvik
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Abstract

This work is dedicated to the study of the discrete version of the Maier-Saupe model in the presence of competing interactions. The competition between interactions favoring different orientational ordering produces a rich phase diagram including modulated phases. Using a mean-field approach and Monte Carlo simulations, we show that the proposed model exhibits isotropic and nematic phases and also a series of modulated phases that meet at a multicritical point, a Lifshitz point. Though the Monte Carlo and mean-field phase diagrams show some quantitative disagreements, the Monte Carlo simulations corroborate the general behavior found within the mean-field approximation.

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P. F. Bienzobaz, Na Xu, Anders W. Sandvik. 2017-07-20. Modulated phases in a three-dimensional Maier-Saupe model with competing interactions. https://doi.org/10.1103/physreve.96.012137

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