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arXiv · 1206.2927

Singular field response and singular screening of vacancies in antiferromagnets

Alexander Wollny·Eric C. Andrade·Matthias Vojta
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Abstract

For isolated vacancies in ordered local-moment antiferromagnets we show that the magnetic-field linear-response limit is generically singular: The magnetic moment associated with a vacancy in zero field is different from that in a finite field h in the limit h->0. The origin is a universal and singular screening cloud, which moreover leads to perfect screening as h->0 for magnets which display spin-flop bulk states in the weak-field limit.

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Alexander Wollny, Eric C. Andrade, Matthias Vojta. 2012-10-24. Singular field response and singular screening of vacancies in antiferromagnets. https://doi.org/10.1103/physrevlett.109.177203

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