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Onset of metallic ferromagnetism in a doped spin-orbital chain

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 نشر من قبل Maria Daghofer
 تاريخ النشر 2005
  مجال البحث فيزياء
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Starting from a spin-orbital model for doped manganites, we investigate a competition between ferromagnetic and antiferromagnetic order in a one-dimensional model at finite temperature. The magnetic and orbital order at half filling support each other and depend on a small antiferromagnetic superexchange between t_{2g} spins and on an alternating Jahn-Teller potential. The crossover to a metallic ferromagnetic phase found at finite doping is partly suppressed by the Jahn-Teller potential which may localize e_g electrons.


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