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arXiv · 0705.3863

Monte Carlo simulations of ${\rm Rb_2MnF_4}$, a classical Heisenberg antiferromagnet in two-dimensions with dipolar interaction

Chenggang Zhou·D. P. Landau·T. C. Schulthess
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Abstract

We study the phase diagram of a quasi-two dimensional magnetic system ${\rm Rb_2MnF_4}$ with Monte Carlo simulations of a classical Heisenberg spin Hamiltonian which includes the dipolar interactions between ${\rm Mn}^{2+}$ spins. Our simulations reveal an Ising-like antiferromagnetic phase at low magnetic fields and an XY phase at high magnetic fields. The boundary between Ising and XY phases is analyzed with a recently proposed finite size scaling technique and found to be consistent with a bicritical point at T=0. We discuss the computational techniques used to handle the weak dipolar interaction and the difference between our phase diagram and the experimental results.

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Chenggang Zhou, D. P. Landau, T. C. Schulthess. 2007-05-25. Monte Carlo simulations of ${\rm Rb_2MnF_4}$, a classical Heisenberg antiferromagnet in two-dimensions with dipolar interaction. https://doi.org/10.1103/physrevb.76.024433

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