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arXiv · 1105.2455

Double-$\it q$ Order in a Frustrated Random Spin System

Ryo Tamura·Naoki Kawashima
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Abstract

We use the three-dimensional Heisenberg model with site randomness as an effective model of the compound Sr(Fe$_{1-x}$Mn$_x$)O$_2$. The model consists of two types of ions that correspond to Fe and Mn ions. The nearest-neighbor interactions in the ab-plane are antiferromagnetic. The nearest-neighbor interactions along the c-axis between Fe ions are assumed to be antiferromagnetic, whereas other interactions are assumed to be ferromagnetic. From Monte Carlo simulations, we confirm the existence of the double-$\boldsymbol{q}$ ordered phase characterized by two wave numbers, $(πππ)$ and $(π\pi0)$. We also identify the spin ordering pattern in the double-$\boldsymbol{q}$ ordered phase.

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Ryo Tamura, Naoki Kawashima. 2011-05-12. Double-$\it q$ Order in a Frustrated Random Spin System. https://doi.org/10.1088/1742-6596%2F320%2F1%2F012013

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