arXiv 1502.063132015-02-23cond-mat.mtrl-sci

Coupled nonpolar-polar metal-insulator transition in 1:1 SrCrO$_3$/SrTiO$_3$ superlattices: A first-principles study

Yuanjun Zhou, Karin M. Rabe

发表信息：: Phys. Rev. Lett. 115, 106401 (2015)
DOI：: 10.1103/PhysRevLett.115.106401

英文摘要：

Using first principles calculations, we determined the epitaxial-strain dependence of the ground state of the 1:1 SrCrO$_3$/SrTiO$_3$ superlattice. The superlattice layering leads to significant changes in the electronic states near the Fermi level, derived from Cr $t_{2g}$ orbitals. An insulating phase is found when the tensile strain is greater than 2.2\% relative to unstrained cubic SrTiO$_3$. The insulating character is shown to arise from Cr $t_{2g}$ orbital ordering, which is produced by an in-plane polar distortion that couples to the superlattice d-bands and is stabilized by epitaxial strain. This effect can be used to engineer the band structure near the Fermi level in transition metal oxide superlattices.

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