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Physical review. B, Condensed matter

Criticality of theD=2quantum Heisenberg ferromagnet with quenched random anisotropy

Ananias M. Mariz, Constantino Tsallis

Published Jun 1, 1985• 6 citations
Publisher

Abstract

We consider the square-lattice spin-(1/2) anisotropic Heisenberg ferromagnet with interactions whose symmetry can independently (quenched model) and randomly be of two competing types: namely, the isotropic Heisenberg type and the Ising type. Within a real-space renormalization-group framework, we perform a quite precise numerical calculation of the critical frontier, and establish its main asymptotic behaviors. We also characterize the relevant universality classes through the analysis of the correlation-length critical exponent.

DOI
10.1103/physrevb.31.7491

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