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Magnetic properties of quantum Heisenberg ferromagnets with long-range interactions

Hiroki Nakano·Minoru Takahashi
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Abstract

Quantum Heisenberg ferromagnets with long-range interactions decayin as $1/r^p$ in one and two dimensions are investigated by means of the Green's function method. It is shown that there exists a finite-temperature phase transition in the region $d<p<2 d$ for the $d$-dimensional case and that no transitions at any finite temperature exist for $p\ge 2 d$; the critical temperature is also estimated. We study the magnetic properties of this model. We calculate the critical exponents' dependence on $p$; these exponents also satisfy a scaling relation. Some of the results were also found using the modified spin-wave theory and are in remarkable agreement with each other.

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Hiroki Nakano, Minoru Takahashi. 1995-05-16. Magnetic properties of quantum Heisenberg ferromagnets with long-range interactions. https://doi.org/10.1103/physrevb.52.6606

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