Diffusion of Quasiparticles in Superconducting Aluminum Films

Abstract

The diffusion of quasiparticle excitations in superconducting aluminum films has been observed. The measured diffusion constant $D=22.5$ ${\mathrm{cm}}^{2}$ ${\mathrm{sec}}^{\ensuremath{-}1}$ is in good agreement with an estimate based on the normal-state resistivity of the films.