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Bose-Einstein condensation of magnons

M. Crisan·D. Bodea·I. Tifrea·I. Grosu
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Abstract

We use the Renormalization Group method to study the Bose-Einstein condensation of the interacting dilute magnons which appears in three dimensional spin systems in magnetic field. The obtained temperature dependence of the critical field $H_c(T)-H_c(0) \sim T^{2}$ is different from the recent self-consistent Hartree-Fock-Popov calculations (cond-mat/0405422) in which a $T^{3/2}$ dependence was reported . The origin of this difference is discussed in the framework of quantum critical phenomena.

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M. Crisan, D. Bodea, I. Tifrea, I. Grosu. 2004-05-26. Bose-Einstein condensation of magnons. https://arxiv.org/abs/cond-mat/0405619

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