Optical investigation of LaMnO3 thin films: a study of the 2-eV band
| Autor: | Milan Radovic, Alessandro Nucara, Antonio Vecchione, R. Fittipaldi, F. M. Vitucci, F. Miletto Granozio, Paola Maselli, Paolo Calvani |
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| Rok vydání: | 2011 |
| Předmět: |
Materials science
Solid-state physics Hubbard model Condensed matter physics Exciton 02 engineering and technology 021001 nanoscience & nanotechnology Condensed Matter Physics 01 natural sciences Optical conductivity Drude model Electronic Optical and Magnetic Materials Tight binding 0103 physical sciences Transmittance Condensed Matter::Strongly Correlated Electrons 010306 general physics 0210 nano-technology Néel temperature |
| Zdroj: | The European Physical Journal B. 79:435-441 |
| ISSN: | 1434-6036 1434-6028 |
| DOI: | 10.1140/epjb/e2011-10945-0 |
| Popis: | We measure the transmittance of LaMnO3 (LMO) thin films in the spectral range from 10 000 to 38 000 cm-1 as a function of temperature. The optical conductivity obtained from the transmittance data is decomposed into five Drude-Lorentz contributions: three of them show evident changes below the Neel temperature T N $\simeq$ 140 K. We discuss the band assignment in the framework of the tight-binding and of the orbitally degenerate Hubbard models. Our results ascribe the overall low-frequency spectrum of LMO to charge-transfer mechanisms involving the t 2g and e g electrons of the Mn ions, without invoking the presence of excitonic contributions. This finding definitely promotes a Mott-Hubbard scenario for LMO and provides an estimate of the Hamiltonian parameters. |
| Databáze: | OpenAIRE |
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