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arXiv · 1010.5625

Spin-glass transition in bond-disordered Heisenberg antiferromagnets coupled with local lattice distortions on a pyrochlore lattice

Hiroshi Shinaoka·Yusuke Tomita·Yukitoshi Motome
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Abstract

Motivated by puzzling characteristics of spin-glass transitions widely observed in pyrochlore-based frustrated materials, we investigate effects of coupling to local lattice distortions in a bond-disordered antiferromagnet on the pyrochlore lattice by extensive Monte Carlo simulations. We show that the spin-glass transition temperature $\TSG$ is largely enhanced by the spin-lattice coupling, and furthermore, becomes almost independent of $Δ$ in a wide range of the disorder strength $Δ$. The critical property of the spin glass transition is indistinguishable from that of the canonical Heisenberg spin glass in the entire range of $Δ$. These peculiar behaviors are ascribed to a modification of the degenerate manifold from continuous to semidiscrete one by the spin-lattice coupling.

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Hiroshi Shinaoka, Yusuke Tomita, Yukitoshi Motome. 2011-06-21. Spin-glass transition in bond-disordered Heisenberg antiferromagnets coupled with local lattice distortions on a pyrochlore lattice. https://doi.org/10.1103/physrevlett.107.047204

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