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Microwave Spectroscopy of Thermally Excited Quasiparticles in YBa_2Cu_3O_{6.99}

A. Hosseini·R. Harris·Saeid Kamal·P. Dosanjh·J. Preston·Ruixing Liang·W. N. Hardy·D. A. Bonn
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Abstract

We present here the microwave surface impedance of a high purity crystal of $YBa_2Cu_3O_{6.99}$ measured at 5 frequencies between 1 and 75 GHz. This data set reveals the main features of the conductivity spectrum of the thermally excited quasiparticles in the superconducting state. Below 20 K there is a regime of extremely long quasiparticle lifetimes, due to both the collapse of inelastic scattering below $T_c$ and the very weak impurity scattering in the high purity $BaZrO_3$-grown crystal used in this study. Above 20 K, the scattering increases dramatically, initially at least as fast as $T^4$.

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A. Hosseini, R. Harris, Saeid Kamal, P. Dosanjh, J. Preston, Ruixing Liang, W. N. Hardy, D. A. Bonn. 1998-11-03. Microwave Spectroscopy of Thermally Excited Quasiparticles in YBa_2Cu_3O_{6.99}. https://doi.org/10.1103/physrevb.60.1349

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