Fig. 4: Local differential conductance and electron density of states.
From: Superconducting insulators and localization of Cooper pairs
a Differential conductance dI/dV as a function of voltage V measured in Ti−Al tunnel junctions at T ≃ 21 mK for five samples Ti1 to Ti5. A sharp peak is observed at e∣V∣ = Δ + ΔAl. Inset: The same data for sample Ti3 at different temperatures. b Fit of the data for sample Ti3 at T ≃ 21 mK to the theory40. Inset: The density of states ν (in units of the normal density of states at the Fermi energy) as a function of energy E reconstructed for the same sample at the same T. Error bars are smaller than data points.
