Phonon metamorphosis in ferromagnetic manganite films: Probing the evolution of an inhomogeneous state

@article{Hartinger2005PhononMI,
  title={Phonon metamorphosis in ferromagnetic manganite films: Probing the evolution of an inhomogeneous state},
  author={Ch. Hartinger and Franz Mayr and Alois Loidl and Thilo Kopp},
  journal={Physical Review B},
  year={2005},
  volume={71},
  pages={184421}
}
The analysis of phonon anomalies provides valuable information about the cooperative dynamics of lattice, spin and charge degrees of freedom. Significant is the anomalous temperature dependence of the external modes observed in La$_{2/3}$Sr$_{1/3}$MnO$_{3}$ (LSMO) films. The two external modes merge close to the ferromagnetic to paramagnetic transition at $T_C$ and, moreover, two new modes evolve in this temperature range with strong resonances at slightly higher frequencies. We propose that… 
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