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arXiv · 1202.0538

Atomic and electronic structures of FeSe monolayer and bilayer thin films on SrTiO$_3$ (001): a first-principles study

Kai Liu·Zhong-Yi LU·Tao Xiang
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Abstract

By the first-principles electronic structure calculations, we have studied electronic structures of FeSe monolayer and bilayer thin films on SrTiO$_3$ (001) with SrO-termination or TiO$_2$ termination. We find that both FeSe monolayer and bilayer on either termination behave like a slightly doped semiconductor and a collinear antiferromagnetic order on Fe ions. There is no substantial charge transfer between the FeSe layers and the substrate. FeSe is adhered to the SrTiO$_3$ surface by a dipole-dipole interaction. The Fermi surface is mainly the contribution of Fe-3d orbitals. A valence band contributed mainly by the O-$2p$ orbitals in the TiO$_2$ layer is located slightly below the Fermi level, which can become conducting upon a small doping of holes.

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Kai Liu, Zhong-Yi LU, Tao Xiang. 2012-02-02. Atomic and electronic structures of FeSe monolayer and bilayer thin films on SrTiO$_3$ (001): a first-principles study. https://doi.org/10.1103/physrevb.85.235123

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