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arXiv · 1102.5616

Energy-gap dynamics of superconducting NbN thin films studied by time-resolved terahertz spectroscopy

M. Beck·M. Klammer·S. Lang·P. Leiderer·V. V. Kabanov·G. N. Gol'tsman·J. Demsar
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Abstract

Using time-domain Terahertz spectroscopy we performed direct studies of the photoinduced suppression and recovery of the superconducting gap in a conventional BCS superconductor NbN. Both processes are found to be strongly temperature and excitation density dependent. The analysis of the data with the established phenomenological Rothwarf-Taylor model enabled us to determine the bare quasiparticle recombination rate, the Cooper pair-breaking rate and the electron-phonon coupling constant, λ= 1.1 +/- 0.1, which is in excellent agreement with theoretical estimates.

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M. Beck, M. Klammer, S. Lang, P. Leiderer, V. V. Kabanov, G. N. Gol'tsman, J. Demsar. 2011-09-28. Energy-gap dynamics of superconducting NbN thin films studied by time-resolved terahertz spectroscopy. https://doi.org/10.1103/physrevlett.107.177007

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