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arXiv · 0810.3043

Valence-bond theory of highly disordered quantum antiferromagnets

S. Zhou·J. A. Hoyos·V. Dobrosavljevic·E. Miranda
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Abstract

We present a large-N variational approach to describe the magnetism of insulating doped semiconductors based on a disorder-generalization of the resonating-valence-bond theory for quantum antiferromagnets. This method captures all the qualitative and even quantitative predictions of the strong-disorder renormalization group approach over the entire experimentally relevant temperature range. Finally, by mapping the problem on a hard-sphere fluid, we could provide an essentially exact analytic solution without any adjustable parameters.

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S. Zhou, J. A. Hoyos, V. Dobrosavljevic, E. Miranda. 2009-07-31. Valence-bond theory of highly disordered quantum antiferromagnets. https://doi.org/10.1209/0295-5075/87/27003

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