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arXiv · 2309.05576

Reentrant Ferromagnetic Ordering of the Random-Field Heisenberg Model in d>2 Dimensions: Fourier-Legendre Renormalization-Group Theory

Alpar Türkoğlu·A. Nihat Berker
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Abstract

The random-magnetic-field classical Heisenberg model is solved in spatial dimensions d>=2 using the recently developed Fourier-Legendre renormalization-group theory for $4\pi$ steradians continuously orientable spins, with renormalization-group flows of 12,500 variables. The random-magnetic-field Heisenberg model is exactly solved in 10 hierarchical models, for d=2,2.26,2.46,2.58,2.63,2.77,2.89,3. For non-zero random fields, ferromagnetic order is seen for d>2. This ordering shows, at d=3, reentrance as a function of temperature.

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Alpar Türkoğlu, A. Nihat Berker. 2023-09-11. Reentrant Ferromagnetic Ordering of the Random-Field Heisenberg Model in d>2 Dimensions: Fourier-Legendre Renormalization-Group Theory. https://doi.org/10.1103/physreve.109.014114

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