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arXiv · 1911.12121

Phase diagram of a three-dimensional dipolar Ising model with textured Ising axes

V. Russier·J. -J. Alonso
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Abstract

We study from tempered Monte Carlo simulations the magnetic phase diagram of a textured dipolar Ising model on a face centered cubic lattice. The Ising coupling of the model follow the dipole-dipole interaction. The Ising axes are distributed with a uniaxial symmetry along the $\hat{z}$ direction with a gaussian probability density of the polar angles. This distribution provides a quenched disorder realization of the dipolar Ising model making a continuous link between the parallel axes dipoles and the random axes dipole models. As expected the phase diagram presents three distinctive phases: paramagnetic, ferromagnetic and spin-glass. A quasi long range ferromagnetic and a reentrant spin-glass phases are obtained in the vicinity of the ferromagnetic spin-glass line. This model provides a way to predict the magnetic phases of magnetic nanoparticles supracrystals in terms of the texturation of the easy axes distribution in the strong anisotropy limit.

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V. Russier, J. -J. Alonso. 2019-11-27. Phase diagram of a three-dimensional dipolar Ising model with textured Ising axes. https://doi.org/10.1088/1361-648x%2Fab6047

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