Comparison of the Electronic Structures of Two Non-cuprate Layered Transition Metal Oxide Superconductors

E. R. Ylvisaker; K. -W. Lee; W. E. Pickett

doi:10.1016/j.physb.2006.03.057

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arXiv · cond-mat/0512211

Comparison of the Electronic Structures of Two Non-cuprate Layered Transition Metal Oxide Superconductors

E. R. Ylvisaker·K. -W. Lee·W. E. Pickett

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Abstract

Comparison is made of the electronic structure of the little-studied layered transition metal oxide LiNbO$_2$ with that of Na$_x$CoO$_2$, which has attracted tremendous interest since superconductivity was discovered in its hydrate. Although the active transition metal $d$ states are quite different due to different crystal fields and band filling, both systems show a strong change of electronic structure with changes in the distance between the transition metal ion layer and the oxygen layers. The niobate is unusual in having a large second-neighbor hopping amplitude, and a nearest neighbor hopping amplitude that is sensitive to the Nb-O separation. Li$_x$NbO$_2$ also presents the attractive simplicity of a single band triangular lattice system with variable carrier concentration that is superconducting.

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E. R. Ylvisaker, K. -W. Lee, W. E. Pickett. 2005-12-11. Comparison of the Electronic Structures of Two Non-cuprate Layered Transition Metal Oxide Superconductors. https://doi.org/10.1016/j.physb.2006.03.057

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