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arXiv · 1309.2973

Modifying the Electronic Orbitals of Nickelate Heterostructures Via Structural Distortions

Hanghui Chen·Divine P. Kumah·Ankit S. Disa·Frederick J. Walker·Charles H. Ahn·Sohrab Ismail-Beigi
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Abstract

We describe a general materials design approach that produces large orbital energy splittings (orbital polarization) in nickelate heterostructures, creating a two-dimensional single-band electronic surface at the Fermi energy. The resulting electronic structure mimics that of the high temperature cuprate superconductors. The two key ingredients are: (i) the construction of atomic-scale distortions about the Ni site via charge transfer and internal electric fields, and (ii) the use of three component (tri-component) superlattices to break inversion symmetry. We use {\it ab initio} calculations to implement the approach, with experimental verification of the critical structural motif that enables the design to succeed.

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Hanghui Chen, Divine P. Kumah, Ankit S. Disa, Frederick J. Walker, Charles H. Ahn, Sohrab Ismail-Beigi. 2013-09-11. Modifying the Electronic Orbitals of Nickelate Heterostructures Via Structural Distortions. https://doi.org/10.1103/physrevlett.110.186402

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