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Orbiton-mediated multi-phonon scattering in La$_{1-x}$Sr$_x$MnO$_3$

K. -Y. Choi·P. Lemmens·G. Güntherodt·Yu. G. Pashkevich·V. P. Gnezdilov·P. Reutler·L. Pinsard-Gaudart·B. Büchner·A. Revcolevschi
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Abstract

We report on Raman scattering measurements of single crystalline La$_{1-x}$Sr$_x$MnO$_3$ ($x$=0, 0.06, 0.09 and 0.125), focusing on the high frequency regime. We observe multi-phonon scattering processes up to fourth-order which show distinct features: (i) anomalies in peak energy and its relative intensity and (ii) a pronounced temperature-, polarization-, and doping-dependence. These features suggest a mixed orbiton-phonon nature of the observed multi-phonon Raman spectra.

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K. -Y. Choi, P. Lemmens, G. Güntherodt, Yu. G. Pashkevich, V. P. Gnezdilov, P. Reutler, L. Pinsard-Gaudart, B. Büchner, A. Revcolevschi. 2005-03-18. Orbiton-mediated multi-phonon scattering in La$_{1-x}$Sr$_x$MnO$_3$. https://doi.org/10.1103/physrevb.72.024301

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