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Anomalous Self-Energy Effects of the B_1g Phonon in Y_{1-x}(Pr,Ca)_xBa_2Cu_3O_7 Films

A. Bock·S. Ostertun·R. Das Sharma·M. R"ubhausen·K. -O. Subke
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Abstract

In Raman spectra of cuprate superconductors the gap shows up both directly, via a redistribution of the electronic background, the so-called "2Delta peaks", and indirectly, e.g. via the renormalization of phononic excitations. We use a model that allows us to study the redistribution and the related phonon self-energy effects simultaneously. We apply this model to the B_1g phonon of Y_{1-x}(Pr,Ca)_xBa_2Cu_3O_7 films, where Pr or Ca substitution enables us to investigate under- and overdoped samples. While various self-energy effects can be explained by the strength and energy of the 2Δpeaks, anomalies remain. We discuss possible origins of these anomalies.

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A. Bock, S. Ostertun, R. Das Sharma, M. R"ubhausen, K. -O. Subke. 1999-08-25. Anomalous Self-Energy Effects of the B_1g Phonon in Y_{1-x}(Pr,Ca)_xBa_2Cu_3O_7 Films. https://doi.org/10.1103/physrevb.60.3532

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