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Magnetic order and valency at La$_{0.7}$Sr$_{0.3}$MnO$_{3}$/SrTiO$_{3}$ interfaces

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 نشر من قبل Walter Temmerman
 تاريخ النشر 2006
  مجال البحث فيزياء
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We report on first principles calculations of the electronic structure of La$_{0.7}$Sr$_{0.3}$MnO$_{3}$/SrTiO$_{3}$ junction with two possible types of interface terminations. We find that the La$_{0.7}$Sr$_{0.3}$O/TiO$_{2}$ interface preserves the interlayer ferromagnetic coupling between the interface MnO$_{2}$ layer and the bulk. The other interface, MnO$_{2}$/SrO, favours antiferromagnetic coupling with the bulk. By inserting two unit cells of undoped LaMnO$_{3}$ at the interface the ferromagnetism is recovered. This is understood in terms of the doping level and the mobility of carriers near the interface.



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