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Superconductivity-induced changes of the phonon resonances in RBa_2Cu_3O_7 (R=rare earth)

S. Ostertun·J. Kiltz·A. Bock·U. Merkt·T. Wolf
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Abstract

We observe a characteristic energy $\hbarω_{c}\approx 2.1$ eV which separates regions of different behavior of the phonon intensities in the Raman spectra of the $R\rm Ba_2Cu_3O_7$ system. A superconductivity-induced drop of phonon intensities is found for the oxygen modes O(4) and O(2)-O(3) only for excitation energies below $\hbarω_c$. This intensity drop indicates an order parameter which affects energies in the vicinity of $\hbarω_c$.

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S. Ostertun, J. Kiltz, A. Bock, U. Merkt, T. Wolf. 2001-01-15. Superconductivity-induced changes of the phonon resonances in RBa_2Cu_3O_7 (R=rare earth). https://doi.org/10.1103/physrevb.64.064521

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