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Phenomenological description of the microwave surface impedance and complex conductivity of high-$T_c$ single crystals

M. R. Trunin·Yu. A. Nefyodov·H. J. Fink
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Abstract

Measurements of the microwave surface impedance $Z_s(T)=R_s(T)+iX_s(T)$ and of the complex conductivity $σ_s(T)$ of high-quality, high-$T_c$ single crystals of YBCO, BSCCO, TBCCO, and TBCO are analyzed. Experimental data of $Z_s(T)$ and $σ_s(T)$ are compared with calculations based on a modified two-fluid model which includes temperature-dependent quasiparticle scattering and a unique temperature variation of the density of superconducting carriers. We elucidate agreement as well as disagreement of our analysis with the salient features of the experimental data. Existing microscopic models are reviewed which are based on unconventional symmetry types of the order parameter and on novel mechanisms of quasiparticle relaxation.

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M. R. Trunin, Yu. A. Nefyodov, H. J. Fink. 1999-11-14. Phenomenological description of the microwave surface impedance and complex conductivity of high-$T_c$ single crystals. https://doi.org/10.1134/1.1326973

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