Cooperative dynamics in doped manganite films: Phonon anomalies in the ferromagnetic state

  title={Cooperative dynamics in doped manganite films: Phonon anomalies in the ferromagnetic state},
  author={Ch. Hartinger and Franz Mayr and Alois Loidl and Thilo Kopp},
  journal={Physical Review B},
We present optical measurements of phononic excitations in La$_{2/3}$Ca$_{1/3}$MnO$_{3}$ (LCMO) and La$_{2/3}$Sr$_{1/3}$MnO$_{3}$ (LSMO) thin films covering the full temperature range from the metallic ferromagnetic to the insulating paramagnetic phase. All eight phonons expected for the R$\bar{3}$c symmetry in LSMO and 17 out of the expected 25 phonons for the Pnma symmetry in LCMO have been determined. Close to the ferromagnetic-to-paramagnetic transition both compounds reveal an anomalous… 
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Evidence of the Fano resonance in a temperature dependent Raman study of CaCu3Ti4O12 and SrCu3Ti4O12.
  • D. K. Mishra, V. Sathe
  • Chemistry
    Journal of physics. Condensed matter : an Institute of Physics journal
  • 2012
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