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arXiv · 1710.06174

Phase Transitions for Cuboc Orders in Stacked Kagome Heisenberg Systems

Kouichi Seki·Kouichi Okunishi
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Abstract

Using the event-chain Monte Carlo (MC) algorithm, we investigate phase transitions of the stacked Kagome Heisenberg systems with classical vector spins including up to the 3rd-nearest-neighbor couplings. In particular, we focus on two types of non-coplanar spin orders ---cuboc1 and cuboc2 orders, both of which have twelve-sublattice structures accompanying the translational-symmetry breaking. We perform event-chain MC simulations up to L=72, where L represents the linear dimension of the stacked Kagome lattice, and then find that the cuboc1 transition shows 2nd-order-transition behaviors with a tendency to a weak-1st-order transition up to L=72, while the cuboc2 transition is basically described by the 1st-order transition. We then discuss the above transitions in connection with the effective Landau-Ginzburg-Wilson theory with the O(3)xO(3) symmetry.

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Kouichi Seki, Kouichi Okunishi. 2017-10-17. Phase Transitions for Cuboc Orders in Stacked Kagome Heisenberg Systems. https://doi.org/10.7566/jpsj.87.023001

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