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arXiv · 0903.1234

Impurity-induced magnetic order in low dimensional spin gapped materials

J. Bobroff·N. Laflorencie·L. K. Alexander·A. V. Mahajan·B. Koteswararao·P. Mendels
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Abstract

We have studied the effect of non-magnetic Zn impurities in the coupled spin-ladder Bi(Cu1xZnx)2PO6 using 31P NMR, muSR and Quantum Monte Carlo simulations. Our results show that the impurities induce in their vicinity antiferromagnetic polarizations, extending over a few unit cells. At low temperature, these extended moments freeze in a process which is found universal among various other spin-gapped compounds: isolated ladders, Haldane or Spin-Peierls chains. This allows us to propose a simple common framework to explain the generic low-temperature impurity induced freezings observed in low dimensional spin-gapped materials.

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J. Bobroff, N. Laflorencie, L. K. Alexander, A. V. Mahajan, B. Koteswararao, P. Mendels. 2009-07-22. Impurity-induced magnetic order in low dimensional spin gapped materials. https://arxiv.org/abs/0903.1234

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