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Raman Scattering in charge ordered Pr_{0.63}Ca_{0.37}MnO_{3} : Anomalous Temperature Dependence of Linewidth

Rajeev Gupta·G. Venketeswara Pai·A. K. Sood·T. V. Ramakrishnan·C. N. R. Rao
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Abstract

We report the evolution of the Raman active A_g phonon modes in the charge-ordered manganite Pr_{0.63}Ca_{0.37}MnO_{3} as a function of temperature from 300K to 25K. Our studies reveal that the linewidths of A_g(2) and A_g(4) phonons increase as temperature decreases. This anomalous temperature dependence of phonon lineshapes, seen for the first time in charge ordered manganites, can be quantitatively understood in terms of strong spin-phonon coupling involving t_{2g} spins and A_g phonons.

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Rajeev Gupta, G. Venketeswara Pai, A. K. Sood, T. V. Ramakrishnan, C. N. R. Rao. 2002-06-12. Raman Scattering in charge ordered Pr_{0.63}Ca_{0.37}MnO_{3} : Anomalous Temperature Dependence of Linewidth. https://doi.org/10.1209/epl%2Fi2002-00417-3

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