Fig. 2.

First derivative dV/dI characteristic: blow-up of the singularity at eV = Δ₁(Al) + Δ₂(Ti) of two S₁IS₂ junctions with two titanium electrodes of different effective diameters d _eff equal to 31 and 36 nm (indicated in the inset). One can clearly see that for the thinnest titanium electrode, the absolute value of the mean gap $\left|{\tilde{\Delta }}_2\right|$ is smaller and the broadening $\delta \left|{\Delta }_2\right|/\left|{\tilde{\Delta }}_2\right|$ is larger