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arXiv · 1201.4984

Monte Carlo simulations of magnetic ordering in the fcc Kagome lattice

V. Hemmati·M. L. Plumer·J. P. Whitehead·B. W. Southern
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Abstract

Monte Carlo simulation results are reported on magnetic ordering in ABC stacked Kagom\'{e} layers with fcc symmetry for both XY and Heisenberg models which include exchange interactions with the eight near-neighbors. Well known degeneracies of the 2D system persist in the 3D case and analysis of the numerical data provides strong evidence for a fluctuation-driven first-order transition to well-defined long-range order characterized as the layered $q=0$ (120-degree) spin structure. Effects of varying the inter-layer coupling are also examined. The results are relevant to understanding the role of frustration in IrMn$_3$ alloys widely used by the magnetic storage industry as thin-films in the antiferromagnetic pinning layer in GMR and TMR spin valves. Despite the technological importance of this structure, it has not previously been noted that the magnetic Mn-ions of fcc IrMn$_3$ form Kagom\'{e} layers.

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V. Hemmati, M. L. Plumer, J. P. Whitehead, B. W. Southern. 2012-01-24. Monte Carlo simulations of magnetic ordering in the fcc Kagome lattice. https://doi.org/10.1103/physrevb.86.104419

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