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arXiv · 1205.4001

Microscopic understanding of the orbital splitting and its tuning at oxide interfaces

Zhicheng Zhong·Philipp Wissgott·Karsten Held·Giorgio Sangiovanni
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Abstract

By means of a Wannier projection within the framework of density functional theory, we are able to identify the modified c-axis hopping and the energy mismatch between the cation bands as the main source of the $t_{2g}$ splitting around the $Γ$ point for oxide heterostructures, excluding previously proposed mechanisms such as Jahn-Teller distortions or electric field asymmetries. Interfacing LaAlO$_3$, LaVO$_3$, SrVO$_3$ and SrNbO$_3$ with SrTiO$_3$ we show how to tune this orbital splitting, designing heterostructures with more $d_{xy}$ electrons at the interface. Such an "orbital engineering" is the key for controlling the physical properties at the interface of oxide heterostructures.

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Zhicheng Zhong, Philipp Wissgott, Karsten Held, Giorgio Sangiovanni. 2012-05-17. Microscopic understanding of the orbital splitting and its tuning at oxide interfaces. https://doi.org/10.1209/0295-5075%2F99%2F37011

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