Wednesday, May 1, 2013

1304.7815 (Hanghui Chen et al.)

Engineering Correlation Effects via Artificially Designed Oxide
Superlattices
   [PDF]

Hanghui Chen, Chris A. Marianetti, Andrew J. Millis
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.
View original: http://arxiv.org/abs/1304.7815

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