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Static hole in a critical antiferromagnet: field-theoretic renormalization group

Subir Sachdev
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Abstract

We consider the quantum field theory of a single, immobile, spin S hole coupled to a two-dimensional antiferromagnet at a bulk quantum critical point between phases with and without magnetic long-range order. We present an alternative derivation of its two-loop beta function; the results agree completely with earlier work (M. Vojta et al, cond-mat/9912020), and also determine a new anomalous dimension of the hole creation operator.

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Subir Sachdev. 2000-11-14. Static hole in a critical antiferromagnet: field-theoretic renormalization group. https://doi.org/10.1016/s0921-4534(01)00198-8

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