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arXiv · 2201.04184

Effects of spin-orbit interaction and electron correlations in strontium titanate

Sergei Urazhdin·Ekram Towsif·Alexander Mitrofanov
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Abstract

We show that the Bloch states in the conduction band of SrTiO$_3$ arise from the interplay between highly anisotropic hopping in sub-bands derived from the Ti $t_{2g}$ orbitals and spin-orbit coupling that mixes these orbitals. Because of the nearly flat-band characteristics for one of the principal axes, at sufficiently high doping these Bloch states become unstable with respect to electron interactions, resulting in Mott-like singlet correlations. These findings may be relevant to the anomalous electronic properties of SrTiO$_3$, including its unusual superconductivity.

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Sergei Urazhdin, Ekram Towsif, Alexander Mitrofanov. 2022-01-11. Effects of spin-orbit interaction and electron correlations in strontium titanate. https://doi.org/10.1103/physrevb.106.224519

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