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arXiv · 1106.5785

Defect-induced spin-glass magnetism in incommensurate spin-gap magnets

Eric C. Andrade·Matthias Vojta
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Abstract

We study magnetic order induced by non-magnetic impurities in quantum paramagnets with incommensurate host spin correlations. In contrast to the well-studied commensurate case where the defect-induced magnetism is spatially disordered but non-frustrated, the present problem combines strong disorder with frustration and, consequently, leads to spin-glass order. We discuss the crossover from strong randomness in the dilute limit to more conventional glass behavior at larger doping, and numerically characterize the robust short-range order inherent to the spin-glass phase. We relate our findings to magnetic order in both BiCu2PO6 and YBa2Cu3O6.6 induced by Zn substitution.

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Eric C. Andrade, Matthias Vojta. 2012-02-06. Defect-induced spin-glass magnetism in incommensurate spin-gap magnets. https://doi.org/10.1209/0295-5075%2F97%2F37007

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