Structure, magnetization, and resistivity ofLa1−xMxCoO3(M=Ca,Sr, and Ba)
| Autor: | Thomas Lorenz, Markus Kriener, C. Zobel, A. Reichl, K. Berggold, A. Freimuth, Matthias Cwik, J. Baier, H. Kierspel, O. Zabara |
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| Rok vydání: | 2004 |
| Předmět: |
Physics
Magnetization Crystallography Ionic radius Condensed matter physics Electrical resistivity and conductivity Doping Structure (category theory) Ionic bonding Condensed Matter::Strongly Correlated Electrons Strongly correlated material Condensed Matter Physics Electronic Optical and Magnetic Materials |
| Zdroj: | Physical Review B. 69 |
| ISSN: | 1550-235X 1098-0121 |
| DOI: | 10.1103/physrevb.69.094417 |
| Popis: | We present an investigation of the influence of structural distortions in charge-carrier doped ${\mathrm{La}}_{1\ensuremath{-}x}{M}_{x}{\mathrm{CoO}}_{3}$ by substituting ${\mathrm{La}}^{3+}$ with alkaline-earth metals of strongly different ionic sizes, that is, $M={\mathrm{Ca}}^{2+},$ ${\mathrm{Sr}}^{2+},$ and ${\mathrm{Ba}}^{2+},$ respectively. We find that both the magnetic properties and the resistivity change nonmonotonically as a function of the ionic size of M. Doping ${\mathrm{La}}_{1\ensuremath{-}x}{M}_{x}{\mathrm{CoO}}_{3}$ with $M={\mathrm{Sr}}^{2+}$ yields higher transition temperatures to the ferromagnetically ordered states and lower resistivities than doping with either ${\mathrm{Ca}}^{2+}$ or ${\mathrm{Ba}}^{2+}$ having a smaller or larger ionic size than ${\mathrm{Sr}}^{2+},$ respectively. From this observation we conclude that the different transition temperatures and resistivities of ${\mathrm{La}}_{1\ensuremath{-}x}{M}_{x}{\mathrm{CoO}}_{3}$ for different M (of the same concentration $x)$ do not only depend on the varying chemical pressures. The local disorder due to the different ionic sizes of ${\mathrm{La}}^{3+}$ and ${M}^{2+}$ plays an important role, too. |
| Databáze: | OpenAIRE |
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