Electron-lattice interactions in the perovskite LaFe0.5Cr0.5O3 characterized by optical spectroscopy and LDA+U calculations
Journal article, 2009

We use resonance Raman scattering (incident photon energies between 1.8 and 4.13 eV), LDA+U calculations, spectroscopic ellipsometry, and oblique IR reflectivity to characterize the strong electron-phonon interactions in the disordered perovskite LaFe0.5Cr0.5O3. When the photon energy coincides with a Cr to Fe Mott-Hubbard transfer gap around 2.4 eV the electron-phonon interaction is manifested by a Franck-Condon effect with exceptional first- and higher order scattering of a local oxygen breathing mode. At higher incident energies we observe a superposition of Franck-Condon scattering and Fröhlich interaction induced infrared active longitudinal optical two-phonon scattering activated mainly by O to Fe charge transfer. Our results establish LaFe0.5Cr0.5O3 as a model compound for research on electron-phonon interactions in strongly correlated complex systems and show that Franck-Condon scattering in complex solids is not limited to Jahn-Teller active compounds.

Author

Jakob Andreasson

Chalmers, Applied Physics, Condensed Matter Physics

Joakim Holmlund

Chalmers, Applied Physics, Condensed Matter Physics

Stefan G. Singer

Christopher Knee

University of Gothenburg

Ralf Rauer

Chalmers, Applied Physics, Condensed Matter Physics

Benjamin Schulz

Mikael Käll

Chalmers, Applied Physics, Bionanophotonics

Michael Rübhausen

Sten Eriksson

Chalmers, Chemical and Biological Engineering, Environmental Inorganic Chemistry

Lars Börjesson

Chalmers, Applied Physics, Condensed Matter Physics

Alexander Lichtenstein

Physical Review B - Condensed Matter and Materials Physics

1098-0121 (ISSN)

Vol. 80 7 075103 [5 pages-

Subject Categories

Chemical Sciences

DOI

10.1103/PhysRevB.80.075103

More information

Created

10/8/2017