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Observation of the Holstein shift in high $T_c$ superconductors with thermal modulation reflectometry

O. V. Dolgov·A. E. Karakozov·A. A. Mikhailovsky·B. J. Feenstra·D. van der Marel
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Abstract

We use the experimental technique of thermal modulation reflectometry to study the relatively small temperature dependence of the optical conductivity of superconductors. Due to a large cancellation of systematic errors, this technique is shown to a be very sensitive probe of small changes in reflectivity. We analyze thermal modulation reflection spectra of single crystals and epitaxially grown thin films of YBa$_2$Cu$_3$O$_{7-δ}$ and obtain the ${α_tr}^2F(ω)$ function in the normal state, as well as the superconductivity induced changes in reflectivity. We present detailed model calculations, based on the Eliashberg-Migdal extension of the BCS model, which show good qualitative and quantitative agreement with the experimental spectra. VSGD.93.12.th

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O. V. Dolgov, A. E. Karakozov, A. A. Mikhailovsky, B. J. Feenstra, D. van der Marel. 1994-06-27. Observation of the Holstein shift in high $T_c$ superconductors with thermal modulation reflectometry. https://doi.org/10.1016/0921-4534(94)90523-1

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