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arXiv · 1411.7333

First Principles Prediction of Topological Phases in Thin Films of Pyrochlore Iridates

Xiang Hu·Zhicheng Zhong·Gregory A. Fiete
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Abstract

Topological phases have attracted much interest in recent years. While there are a number of three-dimensional materials exhibiting topological properties, there are relatively few two-dimensional examples aside from the well-known quantum Hall systems. Here we make materials-specific predictions for topological phases using density functional theory combined with Hartree-Fock theory that includes the full orbital structure of the relevant iridum $d$-orbitals and the strong but finite spin-orbit coupling strength. We find Y$_2$Ir$_2$O$_7$ bilayer and trilayer films grown along the [111] direction can support topological metallic phases with a direct gap of up to 0.02 eV, which could potentially bring transition metal oxides to the fore as a new class of topological materials with potential applications in oxide electronics.

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Xiang Hu, Zhicheng Zhong, Gregory A. Fiete. 2014-11-26. First Principles Prediction of Topological Phases in Thin Films of Pyrochlore Iridates. https://doi.org/10.1038/srep11072

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