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arXiv · 1304.7815

Engineering Correlation Effects via Artificially Designed Oxide Superlattices

Hanghui Chen·Chris A. Marianetti·Andrew J. Millis
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Abstract

Ab initio calculations are used to predict that a superlattice composed of layers of LaTiO3 and LaNiO3 alternating along the [001] direction is a S=1 Mott insulator with large magnetic moments on the Ni sites, negligible moments on the Ti sites and a charge transfer gap set by the energy difference between Ni d and Ti d states, distinct from conventional Mott insulators. Correlation effects are enhanced on the Ni sites via filling the oxygen p states and reducing the Ni-O-Ni bond angle. Small hole (electron) doping of the superlattice leads to a two-dimensional single-band situation with holes (electrons) residing on Ni dx2-y2 (Ti dxy) orbital and coupled to antiferromagnetically correlated spins in the NiO2 layer.

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Hanghui Chen, Chris A. Marianetti, Andrew J. Millis. 2013-04-29. Engineering Correlation Effects via Artificially Designed Oxide Superlattices. https://doi.org/10.1103/physrevlett.111.116403

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