Finite quasiparticle lifetime in disordered superconductors

作者:Zemlicka M*; Neilinger P; Trgala M; Rehak M; Manca D; Grajcar M; Szabo P; Samuely P; Gazi S; Huebner U; Vinokur V M; Il'ichev E
来源:Physical Review B, 2015, 92(22): 224506.
DOI:10.1103/PhysRevB.92.224506

摘要

We investigate the complex conductivity of a highly disordered MoC superconducting film with k(F)l approximate to 1, where k(F) is the Fermi wave number and l is the mean free path, derived from experimental transmission characteristics of coplanar waveguide resonators in a wide temperature range below the superconducting transition temperature T-c. We find that the original Mattis-Bardeen model with a finite quasiparticle lifetime, tau, offers a perfect description of the experimentally observed complex conductivity. We show that iota is appreciably reduced by scattering effects. Characteristics of the scattering centers are independently found by scanning tunneling spectroscopy and agree with those determined from the complex conductivity.