Unconventional electron states in $\delta$-doped SmTiO$_3$

Frank Lechermann

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arXiv · 1603.01031

Unconventional electron states in $\delta$-doped SmTiO$_3$

Frank Lechermann

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Abstract

The Mott-insulating distorted perovskite SmTiO$_3$, doped with a single SrO layer in a quantum-well architecture is studied by the combination of density functional theory with dynamical mean-field theory. A rich correlated electronic structure in line with recent experimental investigations is revealed by the given realistic many-body approach to a large-unit-cell oxide heterostructure. Coexistence of conducting and Mott-insulating TiO$_2$ layers prone to magnetic order gives rise to multi-orbital electronic transport beyond standard Fermi-liquid theory. First hints towards a pseudogap opening due to electron-electron scattering within a background of ferromagnetic and antiferromagnetic fluctuations are detected.

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Frank Lechermann. 2016-03-03. Unconventional electron states in $\delta$-doped SmTiO$_3$. https://arxiv.org/abs/1603.01031

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