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arXiv · 0712.3391

Quasi-Particle Dynamics in Superconducting Aluminum

Katrin Steinberg·Marc Scheffler·Martin Dressel
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Abstract

The response of superconducting aluminum to electromagnetic radiation is investigated in a broad frequency (45 MHz to 40 GHz) and temperature range ($T>T_c/2$), by measuring the complex conductivity. While the imaginary part probes the superfluid density (Cooper-pairs), the real part monitors the opening of the superconducting energy gap and -- most important here -- the zero-frequency quasi-particle response. Varying the mean free path gives some insight into the dynamics, scattering and coherence effects of the quasi-particles in the superconducting state.

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Katrin Steinberg, Marc Scheffler, Martin Dressel. 2008-05-25. Quasi-Particle Dynamics in Superconducting Aluminum. https://doi.org/10.1103/physrevb.77.214517

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