PT Journal
AU Beck, M
   Klammer, M
   Lang, S
   Leiderer, P
   Kabanov, VV
   Gol'tsman, GN
   Demsar, J
TI Energy-gap dynamics of superconducting NbN thin films studied by time-resolved terahertz spectroscopy
SO Phys. Rev. Lett.
JI Phys. Rev. Lett.
PY 2011
BP 4
VL 107
IS 17
DI 10.1103/PhysRevLett.107.177007
DE NbN thin film; energy gap dynamics
AB 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.
ER