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

TL;DR

This study uses advanced computational methods to explore unconventional electron states in a doped Mott insulator, revealing complex electronic structures, coexistence of conducting and insulating layers, and potential pseudogap phenomena.

Contribution

It provides a detailed theoretical analysis of electron states in δ-doped SmTiO₃, highlighting novel multi-orbital transport and magnetic fluctuation effects.

Findings

Coexistence of conducting and insulating TiO₂ layers with magnetic order

Detection of pseudogap hints due to electron-electron interactions

Rich correlated electronic structure consistent with experiments

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.