Method of effective potential for quantum Heisenberg ferromagnet theory

E. V. Podivilov

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arXiv · cond-mat/9402037

Method of effective potential for quantum Heisenberg ferromagnet theory

E. V. Podivilov

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Abstract

Self - consistent temperature dependence of the average magnetization in quantum Heisenberg ferromagnet is obtained as a first approximation of perturbation theory on an inverse radius by application of the functional method for quantum ferromagnet. The experimental data are compared with the theoretical results for {\bf EuO} ferromagnet. A quantitative agreement is observed between theoretical and experimental results outside interval near Curie temperature. The theory is of critical behavior in the vicinity of Curie temperature $T_c$. Theoretical $T_c$ value itself is agreed with the experimental one with an accuracy of several percents.

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E. V. Podivilov. 1994-02-08. Method of effective potential for quantum Heisenberg ferromagnet theory. https://arxiv.org/abs/cond-mat/9402037

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