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Renormalization-Group Approach to Spin-Wave Theory of Quantum Heisenberg Ferromagnet

Naoum Karchev
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Abstract

The renormalization-group method is used to analyze the low-temperature behaviour of a two-dimentional, spin-$s$ quantum Heisenberg ferromagnet. A set of recursion equations is derived in an one-loop approximation. The low-temperature asymptotics of the correlation length and the uniform susceptibility are obtained. For small spins ($s= 1/2,1$) the results are essentially different from those in the spin-wave theory.

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Naoum Karchev. 1996-03-18. Renormalization-Group Approach to Spin-Wave Theory of Quantum Heisenberg Ferromagnet. https://doi.org/10.1103/physrevb.55.6372

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