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

paper

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

arXiv:cond-mat/0512211 · doi:10.1016/j.physb.2006.03.057

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.

5 pages, 3 embedded figures (Proceedings in third Hiroshima international workshop)