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arXiv · 1910.11833

Anisotropic exchange in GdGa

V. S. R. de Sousa·E. P. Nóbrega·P. O. Ribeiro·B. P. Alho·P. J. von Ranke
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Abstract

In this work we discuss the non-collinear ground-state reported for GdGa on the basis of a model Hamiltonian considering anisotropic exchange interactions. We show that a competition between intra and inter-sublattice exchange interactions can lead to a canted structure, which competes with a collinear (ferro or antiferromagnetic) order. The mean-field thermodynamic analysis of the model for $S=7/2$ shows a good agreement between calculated and reported experimental data of the canting angle and isothermal entropy change for GdGa.

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V. S. R. de Sousa, E. P. Nóbrega, P. O. Ribeiro, B. P. Alho, P. J. von Ranke. 2019-10-25. Anisotropic exchange in GdGa. https://doi.org/10.1016/j.jallcom.2020.154119

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