Effects of local oxygen distortions on electronic structures of Na_xCoO₂

2003/05/19 by N. Jun, Ni Jun, Jun, N. +3
Materials Science · Physics and Astronomy · #FOS: Physical sciences #Magnetic and transport properties of perovskites and related materials #Materials Science (cond-mat.mtrl-sci) #Physics of Superconductivity and Magnetism #Superconductivity (cond-mat.supr-con) #ZnO doping and properties #cond-mat.mtrl-sci #cond-mat.supr-con

paper · pdf · doi:10.48550/arxiv.cond-mat/0305423

Revtex 4, 3 pages, 5 figures; the title has been changed to be specific

openalex publication_date 2003/05/19 · arxiv created 2003/09/01 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28

Abstract

By using pseudopotential method with local spin density functional approximation, the electronic band structures of Na_xCoO₂ are calculated for x=0.25, 0.5, 0.75, and x=1 in the presence of the structure relaxations. As increasing Na content, the hybridization between cobalt and oxygen orbitals is decreased, and a phase transition is predicted from a wide-band ferromagnetic to a narrow band paramagnetic metals. The itinerant ferromagnetism is strongly suppressed by the local distortions of the oxygens around the cobalts. Moreover, straining the CoO₂ layers corresponding to the hydrated superconductor Na_0.35CoO₂⋅ 1.3H%₂O strongly enhances both the hybridization and ferromagnetism.

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