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Ferromagnetism in one dimension: Critical Temperature

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 نشر من قبل Pedro Orellana
 تاريخ النشر 2005
  مجال البحث فيزياء
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Ferromagnetism in one dimension is a novel observation which has been reported in a recent work (P. Gambardella et.al., Nature {bf 416}, 301 (2002)), anisotropies are responsibles in that relevant effect. In the present work, another approach is used to obtain transition between two different magnetic ordering phases. Critical temperature has been estimated by Binder method. Ferromagnetic long range interactions have been included in a special Hamiltonian through a power law that decays at large inter-particle distance $r$ as $r^{-alpha}$, where $alphageq0$. For the present model, we have found that the trend of the critical temperature vanishes when the range of interactions decreases ($alphatoinfty$) and close to mean field approximation when the range of interactions increases ($alphato0$). The crossover between two these limit situations is discussed



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