Onset of metallic ferromagnetism in a doped spin-orbital chain
نویسندگان
چکیده
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 t2g 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 eg electrons. [published in phys. stat. sol. 242, 311 (2005)]
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