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arXiv · 1109.2037

Functional-integral approach to the investigation of the spin-spiral magnetic order and phase separation

Anatoly Arzhnikov·Andrey Groshev
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Abstract

We investigate a two-dimensional single-band Hubbard model with a nearest-neighbor hopping. We treat a commensurate collinear order as well as incommensurate spiral magnetic phases at a finite temperature using a Hubbard-Stratonovich transformation with a two-field representation and solve this problem in a static approximation. We argue that temperature dramatically influence the collinear and spiral magnetic phases, phase separation in the vicinity of half-filling. The results imply a possible interpretation of unusual behavior of magnetic properties of single-layer cuprates.

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Anatoly Arzhnikov, Andrey Groshev. 2011-09-09. Functional-integral approach to the investigation of the spin-spiral magnetic order and phase separation. https://arxiv.org/abs/1109.2037

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