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Structural and electronic phenomena at oxyfluoride KTaO$_3$/K$M$F$_3$ ($M$ = Zn and Ni) superlattices: Rashba splitting and 2DEG

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 نشر من قبل Andres Camilo Garcia Castro
 تاريخ النشر 2019
  مجال البحث فيزياء
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Here, we present the theoretical analysis of the structural and electronic degrees of freedom of two different oxide/fluoride perovskite superlattices, KTaO$_3$/KZnF$_3$ and KTaO$_3$/KNiF$_3$. Using first-principles calculations, we found the appearance of a two-dimensional electron, 2DEG, and hole, 2DHG, gases as a function of the number of layers of the different pristine materials. We demonstrate that the phonon-dynamics at the KTO/K$M$F superlattices play a crucial role in the appearance of these effects. Additionally, our results reveal a rather sizeable Rashba-type spin-splitting at these interfaces in comparison to another oxide/oxide counterparts.

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