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Impurity spin dynamics in 2D antiferromagnets and superconductors

Matthias Vojta·Chiranjeeb Buragohain·Subir Sachdev
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Abstract

We discuss the universal theory of localized impurities in the paramagnetic state of 2D antiferromagnets where the spin gap is assumed to be significantly smaller than a typical exchange energy. We study the impurity spin susceptibility near the host quantum transition from a gapped paramagnet to a Neel state, and we compute the impurity-induced damping of the spin-1 mode of the gapped antiferromagnet. Under suitable conditions our results apply also to d-wave superconductors.

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Matthias Vojta, Chiranjeeb Buragohain, Subir Sachdev. 2000-02-20. Impurity spin dynamics in 2D antiferromagnets and superconductors. https://doi.org/10.1016/s0921-4534(00)00503-7

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