Finite-quasiparticle-lifetime effects in the differential conductance of Bi2Sr2CaCu2Oy/Au junctions

Abstract
Bi2 Sr2 CaCu2 Oy/Au point-contact junctions have been studied. For a description of junction properties we used the Blonder-Tinkham-Klapwijk theory where we included the finite lifetime of the quasiparticles. From the fitting procedures of the experimental differential characteristics, the values of the Fermi velocity vF≃5×107 cm/s, the ratio 2Δ/kB Tc≃8, and the coherence length ξab≃35 Å for Bi2 Sr2 CaCu2 Oy were obtained.