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Unconventional electron states in δ-doped SmTiO₃.

ABSTRACT: The Mott-insulating distorted perovskite SmTiO₃, 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 TiO₂ 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.

SUBMITTER: Lechermann F

PROVIDER: S-EPMC5431486 | biostudies-literature | 2017 May

REPOSITORIES: biostudies-literature

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Unconventional electron states in δ-doped SmTiO3.

Lechermann Frank F

Scientific reports 20170508 1

The Mott-insulating distorted perovskite SmTiO3, 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 TiO2 layers prone to magnetic order gives ri ...[more]

PMID: 28484238

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