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Preventing the reconstruction of the polar discontinuity at oxide heterointerfaces

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 نشر من قبل Hans Boschker
 تاريخ النشر 2012
  مجال البحث فيزياء
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Perovskite oxide heteroepitaxy receives much attention because of the possibility to com- bine the diverse functionalities of perovskite oxide building blocks. A general boundary con- dition for the epitaxy is the presence of polar discontinuities at heterointerfaces. These polar discontinuities result in reconstructions, often creating new functionalities at the interface. However, for a significant number of materials these reconstructions are unwanted as they alter the intrinsic materials properties at the interface. Therefore, a strategy to eliminate this reconstruction of the polar discontinuity at the interfaces is required. We show that the use of compositional interface engineering can prevent the reconstruction at the La0.67Sr0.33MnO3/SrTiO3 (LSMO/STO) interface. The polar discontinuity at this interface can be removed by the insertion of a single La0.33Sr0.67O layer, resulting in improved interface magnetization and electrical conductivity.



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