Dome-Shaped Magnetic Phase Diagram of Thermoelectric Layered Cobaltites

2003/10/22 by Jun Sugiyama, J. Sugiyama, J. H. Brewer +14 · 4 citations
Materials Science · Physics and Astronomy · #Advanced Thermoelectric Materials and Devices #Physics of Superconductivity and Magnetism #Thermal Expansion and Ionic Conductivity #cond-mat.mtrl-sci #cond-mat.str-el

paper · pdf · doi:10.1103/physrevlett.92.017602

published as Physical Review Letters 92, 017602 (2004) · 4 pages, 4 figures, 1 table

arxiv created 2003/10/22 · openalex publication_date 2004/01/08 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28

Abstract

Using muon spin spectroscopy we have found that, for both Na_xCoO₂ (0.6\ensuremath≤x\ensuremath≤0.9) and three- and four-layer cobaltites, a common low temperature magnetic state (which in some cases is manifest as an incommensurate spin density wave) forms in the CoO₂ planes. Here we summarize those results and report an almost dome-shaped relation between the transition temperature into the low-T magnetic state and the composition x for Na_xCoO₂ and/or the high-temperature asymptotic limit of thermopower in the more complex three- and four-layer cobaltites. This behavior is explained using the Hubbard model on a two-dimensional triangular lattice in the CoO₂ plane.

Citations

• Topotactic synthesis of highly-textured thermoelectric cobaltites
• Misfit-layered cobaltite with an anisotropic giant magnetoresistance:Ca3Co4O9

Cited by

• Electron correlation in the two-dimensional triangle lattice ofNaxCoO2
• Cascade of Bulk Magnetic Phase Transitions inNaxCoO2as Studied by Muon Spin Rotation
• Changed Circumstances and Pacta Sunt Servanda
• The magnetic field and pressure dependence of the magnetic ordering transition in NaxCoO2(0.6≤x≤0.72)