Charge transfer across transition metal oxide interfaces: emergent conductance and new electronic structure

Hanghui Chen; Hyowon Park; Andrew J. Millis; Chris A. Marianetti

doi:10.1103/physrevb.90.245138

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arXiv · 1408.0217

Charge transfer across transition metal oxide interfaces: emergent conductance and new electronic structure

Hanghui Chen·Hyowon Park·Andrew J. Millis·Chris A. Marianetti

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Abstract

We perform density functional theory plus dynamical mean field theory calculations to investi- gate internal charge transfer in an artificial superlattice composed of alternating layers of vanadate and manganite perovskite and Ruddlesden-Popper structure materials. We show that the elec- tronegativity difference between vanadium and manganese causes moderate charge transfer from VO2 to MnO2 layers in both perovskite and Ruddlesden-Popper based superlattices, leading to hole doping of the VO2 layer and electron doping of the MnO2 layer. Comparison of the perovskite and Ruddlesden-Popper based heterostructures provides insights into the role of the apical oxy- gen. Our first principles simulations demonstrate that the combination of internal charge transfer and quantum confinement provided by heterostructuring is a powerful approach to engineering electronic structure and tailoring correlation effects in transition metal oxides.

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Hanghui Chen, Hyowon Park, Andrew J. Millis, Chris A. Marianetti. 2015-01-02. Charge transfer across transition metal oxide interfaces: emergent conductance and new electronic structure. https://doi.org/10.1103/physrevb.90.245138

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