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On the effects of the magnetic field and the isotopic substitution upon the infrared absorption of manganites

C. A. Perroni·V. Cataudella·G. De Filippis·G. Iadonisi·V. Marigliano Ramaglia·F. Ventriglia
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Abstract

Employing a variational approach that takes into account electron-phonon and magnetic interactions in $La_{1-x}A_xMnO_3$ perovskites with $0<x<0.5$, the effects of the magnetic field and the oxygen isotope substitution on the phase diagram, the electron-phonon correlation function and the infrared absorption at $x=0.3$ are studied. The lattice displacements show a strong correlation with the conductivity and the magnetic properties of the system. Then the conductivity spectra are characterized by a marked sensitivity to the external parameters near the phase boundary.

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C. A. Perroni, V. Cataudella, G. De Filippis, G. Iadonisi, V. Marigliano Ramaglia, F. Ventriglia. 2002-03-06. On the effects of the magnetic field and the isotopic substitution upon the infrared absorption of manganites. https://doi.org/10.1103/physrevb.66.184409

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