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arXiv · 0903.1581

Mangetic phase transition for three-dimensional Heisenberg weak random anisotropy model: Monte Carlo study

Ha M. Nguyen·Pai-Yi Hsiao
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Abstract

Magnetic phase transition (MPT) to magnetic quasi-long-range order (QLRO) phase in a three-dimensional Heisenberg weak (D/J=4) random anisotropy (RA) model is investigated by Monte Carlo simulation. The isotropic and cubic distributions of RA axes are considered for simple-cubic-lattice systems. Finite-size scaling analysis shows that the critical couplings for the former and latter are K_c= 0.70435(2) and K_c=0.70998(4), respectively. While the critical exponent 1/ν=1.40824(0) is the same for both cases. A second-order MPT to the QLRO phase is therefore evidenced to be possible in favor with the existence of the QLRO predicted by recent functional renormalization group theories.

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Ha M. Nguyen, Pai-Yi Hsiao. 2009-03-09. Mangetic phase transition for three-dimensional Heisenberg weak random anisotropy model: Monte Carlo study. https://doi.org/10.1063/1.3068621

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