The thermopower of transition-metal double-perovskites: A sensitive probe of their electronic structures around the Fermi level
| Autor: | George M. Reisner, J. Genossar, Bertina Fisher, K. B. Chashka, Larisa Patlagan |
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| Rok vydání: | 2007 |
| Předmět: |
Materials science
Condensed matter physics Fermi level General Physics and Astronomy Metal Tetragonal crystal system symbols.namesake Crystallography Transition metal Ferrimagnetism Seebeck coefficient visual_art visual_art.visual_art_medium symbols General Materials Science Half-metal Monoclinic crystal system |
| Zdroj: | Current Applied Physics. 7:151-155 |
| ISSN: | 1567-1739 |
| Popis: | We report on a comparative study of S ( T ) for a series of transition-metal double-perovskites A 2 BB′O 6 (A – Ca, Sr, Ba, and B, B′ = transition metal ions), some of them known to have half-metallic ground states. For Sr 2 BB′O 6 with BB′ = CrMo, CrW, CrRe, FeMo, and FeRe (ferrimagnetic with high Curie temperatures), S ( T ) is metallic, for B′ = Mo and W it is n-type and for B′ = Re, p-type. For A 2 FeMoO 6 (A = Ca, Sr, Ba), the crystallographic differences (monoclinic, tetragonal and cubic space-groups, respectively) are accompanied by prominent differences in their (metallic) S ( T ). For the insulating Sr 2 MnReO 6 and Ba 2 MnReO 6 , the onset of ferromagnetic order below T c ∼ 120 K is marked by a steep drop of S ( T ) accompanied by only a slight change in the slope of ln ρ versus 1/ T 1/2 . Significant conclusions were drawn from the experimental results without the need for elaborate models. |
| Databáze: | OpenAIRE |
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